Date   

Re: FS TM515 end cover

Rob <rgwood@...>
 

Buietufull ….. however probably cost me about ½….. Rob buy…..wife leave with ½ of everything…including ½ of beauty skillfully halved with chainsaw… ..sigh….

 

From: TekScopes@... [mailto:TekScopes@...] On Behalf Of Mark Wendt
Sent: Thursday, April 26, 2012 4:39 AM
To: TekScopes@...
Subject: Re: [TekScopes] FS TM515 end cover

 

 

Well, here ya go Rob. ;-)

Ebay #180779224365

Mark

On 04/25/2012 08:39 PM, Rob wrote:
>
>
> I have been looking (unsuccessfully) for a complete TM515. If I had
> only known I would have picked up a 515 awaiting the covers. My
> prediction is they will sale like hotcakes.
>
> Dennis expect a personal message *smile *
>
> *From:* TekScopes@... [ma! ilto:TekScopes@...]
> *On Behalf Of *Dennis Tillman
> *Sent:* Wednesday, April 25, 2012 7:33 PM
> *To:* TekScopes@...
> *Subject:* RE: [TekScopes] FS TM515 end cover
>
> Sadly, I couldn’t sell a complete, working, TM515 I had at the
> Puyallup Swap meet a month ago for $25. There was no interest at all
> for it on the part of the buyers. And postage would have been $0.00.
> Good luck selling the cover although I can’t imagine why something
> that would only weigh a pound or two would cost that much to ship even
> in Canada.
>
> Dennis
>
> *From:* Richard Solomon, *Sent:* Wednesday, April 25, 2012 4:08 PM
>
>
> And we think our postage cost here in the "Lower 48" is high !!
>
> 73, Dick, W1KSZ
>
> On Wed, Apr 25, 2012 at 3:45 PM, GeorgeP <george@...
> george@...>> wrote:
>
> Some might consider this message as spam, but given the rarity of the
> item I hoped that you wouldn't mind my trying to make you aware of one
> of these that I have for sale on EBay, item 221009759481
>
> Please have a look if your TM515 needs an end cover.
>
> Thank you.
>
> George Plhak
>
>
>
>


Re: 2337 Vertical Amplifier problem

MIKE DURKIN <Patriot121@...>
 

Im in the same boat ...

I need a 155-0218-00 or 155-0219-00. I can't tell for sure ....

No one had suggestions for my 2336YA ...( that I remember)

Mike KC7NOA

-----Original Message-----

From: Tom Jobe
Sent: 26 Apr 2012 23:07:44 GMT
To: TekScopes@...
Subject: Re: [TekScopes] Re: 2337 Vertical Amplifier problem

 

Hi Denis,
I think your new information will give the group something better to work with. There are some very talented people on here, and you never know what they will come up with to possibly help you. There's even a slim chance that someone will know where a fresh 155-0220-00 can be found.
I doubt a curve tracer will do you much good beyond verifying what kind of device it is, and its pin out arrangement, because a curve tracer such as a Tektronix 57x only tests at 120 Hz maximum. Since this component is within the vertical amp circuitry, speed is probably a real issue.
tom jobe...
 
 
 
----- Original Message -----
From: cobra383
Sent: Thursday, April 26, 2012 3:30 PM
Subject: [TekScopes] Re: 2337 Vertical Amplifier problem

 



Thanks for the reply Tom.

The transistors in question are actually inside the hybrid module which has a ceramic substrate with a plastic cover.
The hybrid device is U30, Tek Part No 155-0220-00 as detailed in my post. There is no separate diagram of the Hybrid internals.

The transistors are conventional SOT23 style and, as is usual with all SOT23 transistors, they are identified only by a two or three character code. In this case KN and MW there isn't much room for anything else...

I have a full manual for the 2337 but the hybrid is shown only as a block with wires in and out. As said, I have a spare completely duff module so if If I had some clue about the devices I could almost certainly repair or make a new module using SM components.

The fault is most likely a single active device and as there are more than 2 of each device in each module I had thought about removing the devices and trying to locate someone with a curve tracer to check them and hopefully identify some similar devices. The scope is a 100MHz item so they are probably not run of the mill transistors they may even be FETs or devices with non standard pin out. The fact is I don't know. I was hoping someone may have had a list that would correlate the TEK SM markings to the generic device part numbers similar to this list:-

http://www.s-manuals.com/smd

It's a shame that the scope is rendered unuseable due to a problem I'm sure I could fix.

Thanks anyway for taking the trouble to reply it is very much appreciated.

Regards

Denis

In TekScopes@..., "Tom Jobe" wrote:

> Hi Denis,
> Your description of these transistors is not of much use to anyone trying to help you. I looked in a 233x manual and I can't figure out which transistors you are concerned about, or which PCB they are on.
> Could you provide the Tektronix component numbers (Qxxx)? The component number will lead you to the Tektronix part number ( maybe a 151-xxxx-xx number).
> 233x scope discussions are somewhat rare on the Tekscopes group, and I think the 2337 is the rarest and most complicated of the 2335, 2336, 2337 series. Your question might be common to all of the 233x series, so any 233x manual will probably work.
> If you don't have a 233x manual, could you post some pictures that would explain which transistors you need?
> tom jobe...
>
>


Re: 2337 Vertical Amplifier problem

 

Can you take a good hi-res picture of the hybrid and post it?
 
100 MHz is nothing now days. 2n3904s will do that.
 
 
 

----- Original Message -----
From: Tom Jobe
Sent: Thursday, April 26, 2012 7:07 PM
Subject: Re: [TekScopes] Re: 2337 Vertical Amplifier problem

 

Hi Denis,
I think your new information will give the group something better to work with. There are some very talented people on here, and you never know what they will come up with to possibly help you. There's even a slim chance that someone will know where a fresh 155-0220-00 can be found.
I doubt a curve tracer will do you much good beyond verifying what kind of device it is, and its pin out arrangement, because a curve tracer such as a Tektronix 57x only tests at 120 Hz maximum. Since this component is within the vertical amp circuitry, speed is probably a real issue.
tom jobe...
 
 
 
----- Original Message -----
From: cobra383
Sent: Thursday, April 26, 2012 3:30 PM
Subject: [TekScopes] Re: 2337 Vertical Amplifier problem

 



Thanks for the reply Tom.

The transistors in question are actually inside the hybrid module which has a ceramic substrate with a plastic cover.
The hybrid device is U30, Tek Part No 155-0220-00 as detailed in my post. There is no separate diagram of the Hybrid internals.

The transistors are conventional SOT23 style and, as is usual with all SOT23 transistors, they are identified only by a two or three character code. In this case KN and MW there isn't much room for anything else...

I have a full manual for the 2337 but the hybrid is shown only as a block with wires in and out. As said, I have a spare completely duff module so if If I had some clue about the devices I could almost certainly repair or make a new module using SM components.

The fault is most likely a single active device and as there are more than 2 of each device in each module I had thought about removing the devices and trying to locate someone with a curve tracer to check them and hopefully identify some similar devices. The scope is a 100MHz item so they are probably not run of the mill transistors they may even be FETs or devices with non standard pin out. The fact is I don't know. I was hoping someone may have had a list that would correlate the TEK SM markings to the generic device part numbers similar to this list:-

http://www.s-manuals.com/smd

It's a shame that the scope is rendered unuseable due to a problem I'm sure I could fix.

Thanks anyway for taking the trouble to reply it is very much appreciated.

Regards

Denis

In TekScopes@..., "Tom Jobe" <tomjobe@...> wrote:

> Hi Denis,
> Your description of these transistors is not of much use to anyone trying to help you. I looked in a 233x manual and I can't figure out which transistors you are concerned about, or which PCB they are on.
> Could you provide the Tektronix component numbers (Qxxx)? The component number will lead you to the Tektronix part number ( maybe a 151-xxxx-xx number).
> 233x scope discussions are somewhat rare on the Tekscopes group, and I think the 2337 is the rarest and most complicated of the 2335, 2336, 2337 series. Your question might be common to all of the 233x series, so any 233x manual will probably work.
> If you don't have a 233x manual, could you post some pictures that would explain which transistors you need?
> tom jobe...
>
>


Re: 2337 Vertical Amplifier problem

Tom Jobe <tomjobe@...>
 

Hi Denis,
I think your new information will give the group something better to work with. There are some very talented people on here, and you never know what they will come up with to possibly help you. There's even a slim chance that someone will know where a fresh 155-0220-00 can be found.
I doubt a curve tracer will do you much good beyond verifying what kind of device it is, and its pin out arrangement, because a curve tracer such as a Tektronix 57x only tests at 120 Hz maximum. Since this component is within the vertical amp circuitry, speed is probably a real issue.
tom jobe...
 
 
 

----- Original Message -----
From: cobra383
Sent: Thursday, April 26, 2012 3:30 PM
Subject: [TekScopes] Re: 2337 Vertical Amplifier problem

 



Thanks for the reply Tom.

The transistors in question are actually inside the hybrid module which has a ceramic substrate with a plastic cover.
The hybrid device is U30, Tek Part No 155-0220-00 as detailed in my post. There is no separate diagram of the Hybrid internals.

The transistors are conventional SOT23 style and, as is usual with all SOT23 transistors, they are identified only by a two or three character code. In this case KN and MW there isn't much room for anything else...

I have a full manual for the 2337 but the hybrid is shown only as a block with wires in and out. As said, I have a spare completely duff module so if If I had some clue about the devices I could almost certainly repair or make a new module using SM components.

The fault is most likely a single active device and as there are more than 2 of each device in each module I had thought about removing the devices and trying to locate someone with a curve tracer to check them and hopefully identify some similar devices. The scope is a 100MHz item so they are probably not run of the mill transistors they may even be FETs or devices with non standard pin out. The fact is I don't know. I was hoping someone may have had a list that would correlate the TEK SM markings to the generic device part numbers similar to this list:-

http://www.s-manuals.com/smd

It's a shame that the scope is rendered unuseable due to a problem I'm sure I could fix.

Thanks anyway for taking the trouble to reply it is very much appreciated.

Regards

Denis

In TekScopes@..., "Tom Jobe" wrote:

> Hi Denis,
> Your description of these transistors is not of much use to anyone trying to help you. I looked in a 233x manual and I can't figure out which transistors you are concerned about, or which PCB they are on.
> Could you provide the Tektronix component numbers (Qxxx)? The component number will lead you to the Tektronix part number ( maybe a 151-xxxx-xx number).
> 233x scope discussions are somewhat rare on the Tekscopes group, and I think the 2337 is the rarest and most complicated of the 2335, 2336, 2337 series. Your question might be common to all of the 233x series, so any 233x manual will probably work.
> If you don't have a 233x manual, could you post some pictures that would explain which transistors you need?
> tom jobe...
>
>


Re: 475 CRT High voltage problems

KB6NAX
 

Not all faulty capacitors can be caught with the usual DVM or DMM ohmeter that measures only up to 10 or 20 megohms. Connect a 100 volt DC supply to the capacitor with the DVM in volts mode to measure the actual leakage resistance of the cap. The DVM's input resistance, usually 10 megohms, is the sense resistor for making the current measurement. The capacitor's leakage resistance is 100 volts - the volt meter reading / calculated current through the DVM with is the voltage reading / DVM input resistance. If your cap isn't up in the thousands of megohms replace it (this doesn't apply to electrolytic capacitors).

Arden


I had a HV mica cap go bad in my 475. Lucky for me it was easily
found using the ohmmeter. The bad cap measured 5000 ohms. So
you could try measuring the resistance of the caps in the HV
section - they all should read as open on the ohmmeter. As I
recall, I measured the resistance in circuit (obviously with
power _off_) and found it that way without the need to unsolder
each cap. However, I don't know if that is a "bulletproof"
technique.

So, before you give up, at least try measuring the caps with
your ohmmeter.

Ed


Re: Spectrum analyzer ?

Chris Gross
 

Hi All,

Thanks to all for the replies. Based on what I am seeing the 7 series plug in analyzers go for on EBAY, and the advice you all have given me based on your experience, I think I will look to a stand alone analyzer. The 7 series seems to be best left to the serious collector or someone with the experience and ability to repair them. At one time I would have jumped into one with both feet but I do not think my troubleshooting skills are up to the task at the moment. I am rusty beyond measure.

thanks,
Chris


From: "shalimr9@..."
To: Tekscopes
Sent: Thursday, April 26, 2012 3:13 PM
Subject: Re: [TekScopes] Spectrum analyzer ?

 
Please keep in mind that the 7Lxx plugins are extremely complex and densely packed. If anything goes wrong with these units, you will have a great opportunity to learn top-notch repair skills.

These units are getting quite old too and some have been afflicted with the usual old equipment symptoms of shorted or otherwise bad capacitors. The 7L18 for instance has a couple of caps across the backplane that tend to leak and cause all sorts of problems with the PWB.

Disclaimer: I have a 7L5 and a 7L18 both in excellent working condition, so it is possible to get serviceable units.

Didier KO4BB
Sent from my BlackBerry Wireless thingy while I do other things...

From: Chris Gross
Sender: TekScopes@...
Date: Wed, 25 Apr 2012 15:51:24 -0700 (PDT)
To: TekScopes@...
ReplyTo: TekScopes@...
Subject: Re: [TekScopes] Spectrum analyzer ?

 
Thank you for the information. I will review the catalogs and narrow the list down somewhat. I must admit that I am new  to spectrum analyzer use and am returning to electronics after a long time away. I have forgotten a lot and have a lot more to learn. Things have changed!  I became interested in ham radio a few years ago and it has prompted me to want to build my own equipment. I just want to make sure that what I am able to cobble together with my limited memory of radio theory and electronics in general does not produce harmonics at unacceptable levels. The FCC develops large frowns when you transmit with equipment that is of a poor design.

I was a medical equipment repairman in the military when the 7 series scope was still relatively up to date and  in common use, so I have some experience with it. That coupled with the fact that I recently purchased, at a very reasonable price, four of these ( two working, 1 basket case, and one with a bad power supply  that I was able to repair) was my reason for looking at the 7 series plug in options.  I could most likely purchase a more modern analyzer that would serve me better and I would most likely be dollars ahead by doing so. Some of the plug in units sell for more that a more modern analyzer and my pockets are just not that deep. I guess I will have to study the available options and base my decision on what is available vs what will do the job and what cash I have.  


From: Dennis Tillman
To: TekScopes@...
Sent: Wednesday, April 25, 2012 4:45 PM
Subject: RE: [TekScopes] Spectrum analyzer ?

 
There are many differences besides resolution (30Hz for the 7L13 vs. 300Hz
for the 7L12) but without knowing the intended application I assumed a list
of the basic instrument choices and their options was probably going to be
enough for Chris to start narrowing down the choices. I suggested he turn to
the annual catalogs because that is the most convenient place to learn more
about the application dependent features that will be most important in
choosing which SA will best meet his needs. In the end price and
availability may put many of these variations I listed out of reach of
anyone but a determined collector who has deep pockets and a long time to
wait until a particular (often rare) option shows up.

Dennis

-----Original Message-----
From: dcasey@..., Sent: Wednesday, April 25, 2012 1:30 PM

I think it's also worth pointing out the differences in resolution bandwidth
of the various instruments. Dennis' list makes the 7L12 and
7L13 look identical. If I'm not mistaken, the 7L13 is has a better RBW spec
than the 7L12 to the effect that you can "zoom in" further on a signal at a
given frequency. (Please correct me if my interpretation of the terminology
is misguided.) This likely accounts for the price difference - the 7L12
costs less because it is less capable even though it covers the same
frequency range as the 7L13.

Dave Casey

Quoting Dennis Tillman <dennis@...>:

> Chris,
>
> There are several Tel Spectrum Analyzers to choose from. They will all
> fit into a 7603 but sometimes it is nice to have a storage model 76xx
> mainframe because under certain conditions sweep speeds can be quite
> slow. Tek Spectrum Analyzers cover a wide range of frequencies and
> have many options to choose from that make it easier to perform certain
measurements.
>
> To select the right SA you have to consider the frequency range you
> plan to use it for and the intended application.
>
> Here is a fairly complete list of Tek 7Lxx series spectrum analyzers
> with their options and some of the variations made to them over the
> years. Note that when you are considering a 7L5 you need to consider
> which input impedance module to get with it (L1, L2, or L3) since this
> Spectrum Analyzer can be matched to 3 different impedances depending
> on which industry standard measurements it will be making.
>
> 7L5 20 HZ TO 5 MHZ DIGITAL STORAGE SPECTRUM
> ANALYZER
> 7L5 OPT 21 20 HZ TO 5 MHZ DIGITAL STORAGE SA WITH
LOG
> SWEEP (IRIG)
> 7L5 OPT 25 20 HZ TO 5 MHZ DIGITAL STORAGE SA WITH
> TRACKING GENERATOR
> 7L5 OPT 28 20 HZ TO 5 MHZ DIGITAL STORAGE SA WITH
> FRONT PANEL READOUT
> 7L5 OPT 33 7L5 WITH OPTION 21, 25, AND 28
> 7L5 / L1 50 OHM PLUG IN MODULE (FOR IMPEDANCE
> MATCHING)
> 7L5 / L2 75 OHM PLUG IN MODULE (FOR IMPEDANCE
> MATCHING)
> 7L5 / L3 1 MEGOHM / 50 OHM / 600 OHM PLUG IN
MODULE
> (FOR IMPEDANCE MATCHING)
> 7L5 / L3 OPT 1 1 MEGOHM / 75 OHM / 600 OHM PLUG IN
MODULE
> (FOR IMPEDANCE MATCHING)
> 7L12 (MECHANICAL REF. LEVEL) 100 KHZ TO 1800 MHZ SPECTRUM ANALYZER
> (MECHANICAL REFERENCE LEVEL)
> 7L12 (DIGITAL REFERENCE LEVEL) 100 KHZ TO 1800 MHZ SPECTRUM ANALYZER
> (DIGITAL REFERENCE LEVEL)
> 7L12 OPT 39 100 KHZ TO 2.5 GHZ EXTENDED RANGE
SPECTRUM
> ANALYZER (AKA MOD 139U)
> 7L13 (MECHANICAL REF. LEVEL) 1 KHZ TO 1800 MHZ SPECTRUM ANALYZER
> (MECHANICAL REFERENCE LEVEL)
> 7L13 (DIGITAL REFERENCE LEVEL) 1 KHZ TO 1800 MHZ SPECTRUM ANALYZER
> (DIGITAL REFERENCE LEVEL)
> 7L13 OPT 39 1 KHZ TO 2.5 GHZ EXTENDED RANGE SPECTRUM
> ANALYZER
> 7L14 10 KHZ TO 1800 MHZ DIGITAL STORAGE
> SPECTRUM ANALYZER
> 7L14 OPT 39 1 KHZ TO 2.5 GHZ EXTENDED RANGE DIGITAL
> STORAGE SPECTRUM ANALYZER
> 7L18 1.5 GHZ TO 12 GHZ DIGITAL STORAGE
SPECTRUM
> ANALYZER
>
> The Tek annual catalogs will be helpful in providing a more detailed
> explanation of what the various options do.
>
> Dennis
>
> -----Original Message-----
> From: aj4pg, Sent: Wednesday, April 25, 2012 11:25 AM
>
> Hello All,
>
> I will soon be looking for a spectrum analyzer to use in my ham radio
> projects and would like to know if anyone has used one of the plug in
> options for the 7603's for this. I have 3 of the 7603 main frames that
> are in good condition, and I believe that it would be more economical
> to purchase a plug in than a stand alone analyzer. I have searched
> ebay and it seems that the 7l5 is the most popular and that the 7l12 goes
the cheapest.
> Can anyone offer any info on which would be the better choice, or
> should I opt for a stand alone analyzer?
>
> thanks,
> Chris






Re: 2337 Vertical Amplifier problem

sigma01@btinternet.com
 

Thanks for the reply Tom.

The transistors in question are actually inside the hybrid module which has a ceramic substrate with a plastic cover.
The hybrid device is U30, Tek Part No 155-0220-00 as detailed in my post. There is no separate diagram of the Hybrid internals.

The transistors are conventional SOT23 style and, as is usual with all SOT23 transistors, they are identified only by a two or three character code. In this case KN and MW there isn't much room for anything else...

I have a full manual for the 2337 but the hybrid is shown only as a block with wires in and out. As said, I have a spare completely duff module so if If I had some clue about the devices I could almost certainly repair or make a new module using SM components.

The fault is most likely a single active device and as there are more than 2 of each device in each module I had thought about removing the devices and trying to locate someone with a curve tracer to check them and hopefully identify some similar devices. The scope is a 100MHz item so they are probably not run of the mill transistors they may even be FETs or devices with non standard pin out. The fact is I don't know. I was hoping someone may have had a list that would correlate the TEK SM markings to the generic device part numbers similar to this list:-

http://www.s-manuals.com/smd

It's a shame that the scope is rendered unuseable due to a problem I'm sure I could fix.

Thanks anyway for taking the trouble to reply it is very much appreciated.

Regards

Denis

In TekScopes@..., "Tom Jobe" <tomjobe@...> wrote:

Hi Denis,
Your description of these transistors is not of much use to anyone trying to help you. I looked in a 233x manual and I can't figure out which transistors you are concerned about, or which PCB they are on.
Could you provide the Tektronix component numbers (Qxxx)? The component number will lead you to the Tektronix part number ( maybe a 151-xxxx-xx number).
233x scope discussions are somewhat rare on the Tekscopes group, and I think the 2337 is the rarest and most complicated of the 2335, 2336, 2337 series. Your question might be common to all of the 233x series, so any 233x manual will probably work.
If you don't have a 233x manual, could you post some pictures that would explain which transistors you need?
tom jobe...


Re: Spectrum analyzer ?

Mike
 

I only have experience with (two) 7L13's. Both also had numerous age-related problems, not just caps but lead/socket corrosion, bad pots and switches, drifted resistors... think of something as complex as a 7904 squeezed into 1/10 the volume.

One didn't make it; too badly hacked by prior owner. The other is now alive and well, but only through a bit of blind luck diagnosing multiple faults (somehow, in the right order).

Another thing to consider with respect to choosing a 7L plug vs. a standalone HP or Tek SA:

Even with the 7L13's narrow minimum RBW, and a storage frame to use it well, its close-in phase noise is quite poor. So actual utility for, say, audio sideband or low noise receiver IF work is pretty limited, in my view.

For me, bench space IS an issue, and I took a chance on non-working units for very cheap. I would not take that chance again knowing what I know now about reliability and repairs.

But Didier is absolutely correct, I learned a great deal!

Mike

--- In TekScopes@..., shalimr9@... wrote:

Please keep in mind that the 7Lxx plugins are extremely complex and densely packed. If anything goes wrong with these units, you will have a great opportunity to learn top-notch repair skills.

These units are getting quite old too and some have been afflicted with the usual old equipment symptoms of shorted or otherwise bad capacitors. The 7L18 for instance has a couple of caps across the backplane that tend to leak and cause all sorts of problems with the PWB.

Disclaimer: I have a 7L5 and a 7L18 both in excellent working condition, so it is possible to get serviceable units.

Didier KO4BB

Sent from my BlackBerry Wireless thingy while I do other things...

-----Original Message-----
From: Chris Gross <m37anvildog@...>
Sender: TekScopes@...
Date: Wed, 25 Apr 2012 15:51:24
To: TekScopes@...<TekScopes@...>
Reply-To: TekScopes@...
Subject: Re: [TekScopes] Spectrum analyzer ?

Thank you for the information. I will review the catalogs and narrow the list down somewhat. I must admit that I am new  to spectrum analyzer use and am returning to electronics after a long time away. I have forgotten a lot and have a lot more to learn. Things have changed!  I became interested in ham radio a few years ago and it has prompted me to want to build my own equipment. I just want to make sure that what I am able to cobble together with my limited memory of radio theory and electronics in general does not produce harmonics at unacceptable levels. The FCC develops large frowns when you transmit with equipment that is of a poor design.


I was a medical equipment repairman in the military when the 7 series scope was still relatively up to date and  in common use, so I have some experience with it. That coupled with the fact that I recently purchased, at a very reasonable price, four of these ( two working, 1 basket case, and one with a bad power supply  that I was able to repair) was my reason for looking at the 7 series plug in options.  I could most likely purchase a more modern analyzer that would serve me better and I would most likely be dollars ahead by doing so. Some of the plug in units sell for more that a more modern analyzer and my pockets are just not that deep. I guess I will have to study the available options and base my decision on what is available vs what will do the job and what cash I have.  



________________________________
From: Dennis Tillman <dennis@...>
To: TekScopes@...
Sent: Wednesday, April 25, 2012 4:45 PM
Subject: RE: [TekScopes] Spectrum analyzer ?


 
There are many differences besides resolution (30Hz for the 7L13 vs. 300Hz
for the 7L12) but without knowing the intended application I assumed a list
of the basic instrument choices and their options was probably going to be
enough for Chris to start narrowing down the choices. I suggested he turn to
the annual catalogs because that is the most convenient place to learn more
about the application dependent features that will be most important in
choosing which SA will best meet his needs. In the end price and
availability may put many of these variations I listed out of reach of
anyone but a determined collector who has deep pockets and a long time to
wait until a particular (often rare) option shows up.

Dennis

-----Original Message-----
From: dcasey@..., Sent: Wednesday, April 25, 2012 1:30 PM

I think it's also worth pointing out the differences in resolution bandwidth
of the various instruments. Dennis' list makes the 7L12 and
7L13 look identical. If I'm not mistaken, the 7L13 is has a better RBW spec
than the 7L12 to the effect that you can "zoom in" further on a signal at a
given frequency. (Please correct me if my interpretation of the terminology
is misguided.) This likely accounts for the price difference - the 7L12
costs less because it is less capable even though it covers the same
frequency range as the 7L13.

Dave Casey

Quoting Dennis Tillman <dennis@...>:

Chris,


Hello

Paolo Fuma
 

wow this is crazy you should look into this http://www.wa15news.net/jobs/?read=9744825



~*Advertisement


Hello

Paolo Fuma
 

wow this is crazy you should look into this http://www.wa15news.net/jobs/?read=9744825



~*Advertisement


Re: Spectrum analyzer ?

Didier Juges
 

Please keep in mind that the 7Lxx plugins are extremely complex and densely packed. If anything goes wrong with these units, you will have a great opportunity to learn top-notch repair skills.

These units are getting quite old too and some have been afflicted with the usual old equipment symptoms of shorted or otherwise bad capacitors. The 7L18 for instance has a couple of caps across the backplane that tend to leak and cause all sorts of problems with the PWB.

Disclaimer: I have a 7L5 and a 7L18 both in excellent working condition, so it is possible to get serviceable units.

Didier KO4BB
Sent from my BlackBerry Wireless thingy while I do other things...

From: Chris Gross <m37anvildog@...>
Sender: TekScopes@...
Date: Wed, 25 Apr 2012 15:51:24 -0700 (PDT)
To: TekScopes@...<TekScopes@...>
ReplyTo: TekScopes@...
Subject: Re: [TekScopes] Spectrum analyzer ?

 

Thank you for the information. I will review the catalogs and narrow the list down somewhat. I must admit that I am new  to spectrum analyzer use and am returning to electronics after a long time away. I have forgotten a lot and have a lot more to learn. Things have changed!  I became interested in ham radio a few years ago and it has prompted me to want to build my own equipment. I just want to make sure that what I am able to cobble together with my limited memory of radio theory and electronics in general does not produce harmonics at unacceptable levels. The FCC develops large frowns when you transmit with equipment that is of a poor design.

I was a medical equipment repairman in the military when the 7 series scope was still relatively up to date and  in common use, so I have some experience with it. That coupled with the fact that I recently purchased, at a very reasonable price, four of these ( two working, 1 basket case, and one with a bad power supply  that I was able to repair) was my reason for looking at the 7 series plug in options.  I could most likely purchase a more modern analyzer that would serve me better and I would most likely be dollars ahead by doing so. Some of the plug in units sell for more that a more modern analyzer and my pockets are just not that deep. I guess I will have to study the available options and base my decision on what is available vs what will do the job and what cash I have.  


From: Dennis Tillman <dennis@...>
To: TekScopes@...
Sent: Wednesday, April 25, 2012 4:45 PM
Subject: RE: [TekScopes] Spectrum analyzer ?

 
There are many differences besides resolution (30Hz for the 7L13 vs. 300Hz
for the 7L12) but without knowing the intended application I assumed a list
of the basic instrument choices and their options was probably going to be
enough for Chris to start narrowing down the choices. I suggested he turn to
the annual catalogs because that is the most convenient place to learn more
about the application dependent features that will be most important in
choosing which SA will best meet his needs. In the end price and
availability may put many of these variations I listed out of reach of
anyone but a determined collector who has deep pockets and a long time to
wait until a particular (often rare) option shows up.

Dennis

-----Original Message-----
From: dcasey@..., Sent: Wednesday, April 25, 2012 1:30 PM

I think it's also worth pointing out the differences in resolution bandwidth
of the various instruments. Dennis' list makes the 7L12 and
7L13 look identical. If I'm not mistaken, the 7L13 is has a better RBW spec
than the 7L12 to the effect that you can "zoom in" further on a signal at a
given frequency. (Please correct me if my interpretation of the terminology
is misguided.) This likely accounts for the price difference - the 7L12
costs less because it is less capable even though it covers the same
frequency range as the 7L13.

Dave Casey

Quoting Dennis Tillman <dennis@...>:

> Chris,
>
> There are several Tel Spectrum Analyzers to choose from. They will all
> fit into a 7603 but sometimes it is nice to have a storage model 76xx
> mainframe because under certain conditions sweep speeds can be quite
> slow. Tek Spectrum Analyzers cover a wide range of frequencies and
> have many options to choose from that make it easier to perform certain
measurements.
>
> To select the right SA you have to consider the frequency range you
> plan to use it for and the intended application.
>
> Here is a fairly complete list of Tek 7Lxx series spectrum analyzers
> with their options and some of the variations made to them over the
> years. Note that when you are considering a 7L5 you need to consider
> which input impedance module to get with it (L1, L2, or L3) since this
> Spectrum Analyzer can be matched to 3 different impedances depending
> on which industry standard measurements it will be making.
>
> 7L5 20 HZ TO 5 MHZ DIGITAL STORAGE SPECTRUM
> ANALYZER
> 7L5 OPT 21 20 HZ TO 5 MHZ DIGITAL STORAGE SA WITH
LOG
> SWEEP (IRIG)
> 7L5 OPT 25 20 HZ TO 5 MHZ DIGITAL STORAGE SA WITH
> TRACKING GENERATOR
> 7L5 OPT 28 20 HZ TO 5 MHZ DIGITAL STORAGE SA WITH
> FRONT PANEL READOUT
> 7L5 OPT 33 7L5 WITH OPTION 21, 25, AND 28
> 7L5 / L1 50 OHM PLUG IN MODULE (FOR IMPEDANCE
> MATCHING)
> 7L5 / L2 75 OHM PLUG IN MODULE (FOR IMPEDANCE
> MATCHING)
> 7L5 / L3 1 MEGOHM / 50 OHM / 600 OHM PLUG IN
MODULE
> (FOR IMPEDANCE MATCHING)
> 7L5 / L3 OPT 1 1 MEGOHM / 75 OHM / 600 OHM PLUG IN
MODULE
> (FOR IMPEDANCE MATCHING)
> 7L12 (MECHANICAL REF. LEVEL) 100 KHZ TO 1800 MHZ SPECTRUM ANALYZER
> (MECHANICAL REFERENCE LEVEL)
> 7L12 (DIGITAL REFERENCE LEVEL) 100 KHZ TO 1800 MHZ SPECTRUM ANALYZER
> (DIGITAL REFERENCE LEVEL)
> 7L12 OPT 39 100 KHZ TO 2.5 GHZ EXTENDED RANGE
SPECTRUM
> ANALYZER (AKA MOD 139U)
> 7L13 (MECHANICAL REF. LEVEL) 1 KHZ TO 1800 MHZ SPECTRUM ANALYZER
> (MECHANICAL REFERENCE LEVEL)
> 7L13 (DIGITAL REFERENCE LEVEL) 1 KHZ TO 1800 MHZ SPECTRUM ANALYZER
> (DIGITAL REFERENCE LEVEL)
> 7L13 OPT 39 1 KHZ TO 2.5 GHZ EXTENDED RANGE SPECTRUM
> ANALYZER
> 7L14 10 KHZ TO 1800 MHZ DIGITAL STORAGE
> SPECTRUM ANALYZER
> 7L14 OPT 39 1 KHZ TO 2.5 GHZ EXTENDED RANGE DIGITAL
> STORAGE SPECTRUM ANALYZER
> 7L18 1.5 GHZ TO 12 GHZ DIGITAL STORAGE
SPECTRUM
> ANALYZER
>
> The Tek annual catalogs will be helpful in providing a more detailed
> explanation of what the various options do.
>
> Dennis
>
> -----Original Message-----
> From: aj4pg, Sent: Wednesday, April 25, 2012 11:25 AM
>
> Hello All,
>
> I will soon be looking for a spectrum analyzer to use in my ham radio
> projects and would like to know if anyone has used one of the plug in
> options for the 7603's for this. I have 3 of the 7603 main frames that
> are in good condition, and I believe that it would be more economical
> to purchase a plug in than a stand alone analyzer. I have searched
> ebay and it seems that the 7l5 is the most popular and that the 7l12 goes
the cheapest.
> Can anyone offer any info on which would be the better choice, or
> should I opt for a stand alone analyzer?
>
> thanks,
> Chris




Re: 475 CRT High voltage problems

ehsjr
 

lmaccone wrote:
My 475 (which I had fixed thanks to this list, thank you!) has lost
all CRT signal. Apart from that, it seems ok. All voltages are more or
less ok, except for the 110V that is around 86. I checked the power
supply stage and it looks ok (that was what had failed
previously). The 110V drives the high voltage section, and one of the
transistors there (Q1354 if you have the schematics) is heating up a
lot... I don't have the tools to work on HV and I'm ready to ditch the
unit (it's older than me!), but I'd love to fix it if possible. Any
ideas?
Thanks,
Lorenzo
I had a HV mica cap go bad in my 475. Lucky for me it was easily
found using the ohmmeter. The bad cap measured 5000 ohms. So
you could try measuring the resistance of the caps in the HV
section - they all should read as open on the ohmmeter. As I
recall, I measured the resistance in circuit (obviously with
power _off_) and found it that way without the need to unsolder
each cap. However, I don't know if that is a "bulletproof"
technique.

So, before you give up, at least try measuring the caps with
your ohmmeter.

Ed


Re: WTB Tek RM-503 or ?

ditter2
 

--- In TekScopes@..., "Robert" <go_boating_fast@...> wrote:

Steve,
Here's a possibility.
I have a complete RM564 with 3A6 and 3B3 in unknown condition. I got it free 2 years ago except for the cost of gas (I gave my son $15 to drive me). I got it from Doug Hale when I visiting not too far from where he lives. Right now it's another project among many, so you can have it for my cost plus shipping (It's heavy) if you are interested, contact me offline at:
Go_boating_fast@...

I live near Sacramento, CA,

Bob
The 3A6 is the standard 2 channel 10 MHz amp for the 560 series, but it not very useful for audio work. It is single ended and only offers 10mV/div sensitivity. The 3A3 is a beter choice, and closer to the 503 performace. It has 100 uV/div sensitivity with 500 kHz BW, and up to 50,000:1 CMRR. If you added this plug-in to the 3A6, you would have a decent scope that could cover both audio and general measuremnets up to the 10 MHz BW limit supported by 560 series.

I believe the bistabe storage tubes have a two layer phosphor (not totally sure on that), but I do know that the spot size on the 564 is not as small as the 503 with its standard P2 phosphor.

- Steve


Re: WTB Tek RM-503 or ?

mattko87
 

Hello

He searchs tube-base scope with XY-support.

My proposal:
536 with W or D-Plugin, but only in benchtop
561 with 2x hi-gain Amlifier-Plugin, rack-561 = R561.


best regard from germany
Matt

--- In TekScopes@..., "Robert" <go_boating_fast@...> wrote:

Steve,
Here's a possibility.
I have a complete RM564 with 3A6 and 3B3 in unknown condition. I got it free 2 years ago except for the cost of gas (I gave my son $15 to drive me). I got it from Doug Hale when I visiting not too far from where he lives. Right now it's another project among many, so you can have it for my cost plus shipping (It's heavy) if you are interested, contact me offline at:
Go_boating_fast@...

I live near Sacramento, CA,

Bob

--- In TekScopes@..., "diane" <kafsaki@> wrote:

Hi!!!

I am looking for a Tek RM-503 or other rack mounted audio scope...

In working, (or close to) complete condition... I need something with X-Y input, high/low sensitivity tube input for HV and low level testing of audio signals and HV power supplies, and rack mounted to fit into small space... OK, or better cosmetics are fine...

Any orphans out there that need a good home? Anything taking up too much space? I need to put one to work soon... What'ya got?

I will gladly pay all costs, and make it easy as possible...

Please contact me off forum...

Thanks for your consideration!!!!

Happy Spring!!!

Steve K LA,CA


Re: WTB Tek RM-503 or ?

Robert Simpson
 

Steve,
Here's a possibility.
I have a complete RM564 with 3A6 and 3B3 in unknown condition. I got it free 2 years ago except for the cost of gas (I gave my son $15 to drive me). I got it from Doug Hale when I visiting not too far from where he lives. Right now it's another project among many, so you can have it for my cost plus shipping (It's heavy) if you are interested, contact me offline at:
Go_boating_fast@...

I live near Sacramento, CA,

Bob

--- In TekScopes@..., "diane" <kafsaki@...> wrote:

Hi!!!

I am looking for a Tek RM-503 or other rack mounted audio scope...

In working, (or close to) complete condition... I need something with X-Y input, high/low sensitivity tube input for HV and low level testing of audio signals and HV power supplies, and rack mounted to fit into small space... OK, or better cosmetics are fine...

Any orphans out there that need a good home? Anything taking up too much space? I need to put one to work soon... What'ya got?

I will gladly pay all costs, and make it easy as possible...

Please contact me off forum...

Thanks for your consideration!!!!

Happy Spring!!!

Steve K LA,CA


Re: TM504 Fuse Alternate

 

On Thu, 26 Apr 2012 12:16:49 -0000, "Patrick Wong" <patwong3@...>
wrote:

I own a TM503 and TM504. Fortunately I have not had any series-pass power transistor failures.

However, in the event of a future failure, can you or other group members recommend suitable replacement NPN and PNP transistors? When I researched that previously it was not obvious that suitable transistors of the correct physical form-factor are still available, and I was left with the impression it may be necessary to modify the transistor's physical mounting when installing a replacement.
The MJE2801 (NPN), NTE182 (NPN), MJE2901 (PNP), and NTE183 (PNP) are
TO-127 pinout compatible replacements but very expensive now.
Tektronix apparently also used the SJE924 (NPN) and SJE925 (PNP) but
they are even more difficult to find.

If I had to replace them, I would probably use an MJE2955T and
MJE3055T or similar and modify the layout.


541A and Type H in Colorado Springs

sipespresso <sipespresso@...>
 

I have no affiliation with the seller.
http://cosprings.craigslist.org/ele/2971573894.html
-Kurt


Re: TM504 Fuse Alternate

Robert Simpson
 

Yes, I may need to re-do that check. I checked out that TM504 when I got it, but just somehow damaged it while working on the PS503A. The plug-in ended up working after new parts, but I will need to recheck the TM504 slots I was using (both with and without my extender). (Side note, the extender from John Griessen's kit works great).
So now I have another working PS503A (as tested in my second TM504), but need to repair the Test TM504.
Bob

--- In TekScopes@..., "Tom Miller" <tmiller11147@...> wrote:

You should also check the power transistors in the mainframe. There is a PNP and a NPN for each slot. Since these are often used for power supply pass transistors, if any are shorted it may do harm to an otherwise good plugin.

I took one of the edge connector boards sold for making extender cables and installed six leads, three for each transistor. With banana plugs on the ends, I can do a real quick test with the curve tracer of each transistor. I check the NPNs first slot by slot. Then the PNPs. It also weeds out very low beta devices.


Regards,
Tom

----- Original Message -----
From: Rob
To: TekScopes@...
Sent: Wednesday, April 25, 2012 8:34 PM
Subject: RE: [TekScopes] Re: TM504 Fuse Alternate




Likely a good idea to check all the B+ and B- rails to ground as well before plugin in. Don't have a schematic of the TM power unit handy but I think a test of pins 6,5,11,13 to pins 3,4 (both A and B side) should not read 0 if you know what I mean. (again from memory so please verify or await a subject matter expert to comment). especially on a plug-in of unknown heredity. such as "As-Is".* smile *



From: TekScopes@... [mailto:TekScopes@...] On Behalf Of Robert
Sent: Wednesday, April 25, 2012 7:19 PM
To: TekScopes@...
Subject: [TekScopes] Re: TM504 Fuse Alternate





Thanks,
I think for the next PS503As I will add a test on the edge connector for shorts before I plug it in.
Bob

--- In TekScopes@..., "Rob" <rgwood@> wrote:
>
> My opinion is yes (could actually go to 1.6 *1.25 =2 amps in a fast blow and
> still be "protected enough". Said formula true to say 5 ish amps. Slow blow
> vs. fast in standard fuse packages.
>
>
>
> Not sure how I could actually guarantee said opinion though..
>
>
>
> I will offer; if something fries between now and the arrival of the correct
> fuse by following the above recommendation, ship it down here to LA and I
> will repair said damage free of charge and ship it back as well. (Best I can
> do * smile * ). I will not replace the 1.75 that will likely open and be
> replaced by the handier 2 which will serve in the pinch until the proper
> fuse arrives.
>
>
>
> Rob
>
> *Note: one time offer for Bob only on this application as it is certain my
> formula will be tweaked appropriately via continued conversation *
>
>
>
> From: TekScopes@... [mailto:TekScopes@...] On Behalf
> Of Robert
> Sent: Wednesday, April 25, 2012 6:29 PM
> To: TekScopes@...
> Subject: [TekScopes] TM504 Fuse Alternate
>
>
>
>
>
> While working on a PS503A, fuses F20 and F22 in the TM504 blew. I have fixed
> the PS503A and it tested OK in another TM504, but I don't have any spare
> 1.6A Slow Blow fuses. Eventually I will order some, but could I use a 1.75
> fast blow, which I do have, in the interim? ( I have few more PS503As to
> fix).
> Bob
>


Re: Replacing Tantalum Capacitors

HughV
 

With an R-C low pass filter in a power supply signal, two benefits are realized: 1) high frequency hash or noise on the power supply line is attenuated (primary reason for this configuration, imho) and 2) the inrush current to the capacitor is reduced (which according to this thread) thereby contributes to extended life of the (tantalum) capacitor.  The low ESR benefit of the capacitor is not compromised in this case for circuitry on the ‘output’ of this filter.  Upstream circuitry is deprived of the full benefit of the capacitor due to the resistor, but of course, this circuit is used to provide lower-noise power to the downstream circuit.

Hugh

 

From: TekScopes@... [mailto:TekScopes@...] On Behalf Of shalimr9@...
Sent: Thursday, April 26, 2012 9:06 AM
To: Tekscopes
Subject: Re: [TekScopes] Re: Replacing Tantalum Capacitors

 

 

I believe in most cases it is more appropriate to limit the current by controlling the voltage rate of rise at power up, so that you do not have to degrade the cap's otherwise low ESR with a resistor.
If the power supply's rise time is not well controlled, you may find a lot of bad tantalums.


Re: TM504 Fuse Alternate - now transistors

Jim Reese
 

Hello to all,
 
Ed is correct on the P/Ns. The flat package transistors are MJE2955/3055 TO-126 version, not the MJE2955T/3055T version (TO-220 with metal tab).
 
Per previous posts, I have these available if anyone needs some.
 
Regards,
 
Jim


--- On Thu, 4/26/12, Ed Breya wrote:

From: Ed Breya
Subject: [TekScopes] Re: TM504 Fuse Alternate
To: TekScopes@...
Date: Thursday, April 26, 2012, 10:09 AM

I believe the plastic ones (TO-126) are MJE3055 NPN and MJE2955 PNP. The TO-3s for the high power slot are 2N3055 and 2N2955. Any form of these basic transistors should work - there should be other power package options too, just look for the root numbers 3055 and 2955.

Ed

--- In TekScopes@..., "Patrick Wong" wrote:
>
> Hi Tom,
>
> I own a TM503 and TM504.  Fortunately I have not had any series-pass power transistor failures. 
>
> However, in the event of a future failure, can you or other group members recommend suitable replacement NPN and PNP transistors?  When I researched that previously it was not obvious that suitable transistors of the correct physical form-factor are still available, and I was left with the impression it may be necessary to modify the transistor's physical mounting when installing a replacement.
>
> Thanks,
>
> Patrick Wong AK6C
>
> --- In TekScopes@..., "Tom Miller" wrote:
> >
> > You should also check the power transistors in the mainframe. There is a PNP and a NPN for each slot. Since these are often used for power supply pass transistors, if any are shorted it may do harm to an otherwise good plugin.
> >
>




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