Date   

Re: My first scope, a Tektronix 11401 with option 2D extended memory and two 11A34 plugins and an 11A33 plugin.

Jim Ford
 

114XX I have no interest in, but 118XX I do.  Having used a CSA803 at work (as well as an HP 54120) several decades ago, I would love to have a 118XX in my garage lab.  Tek beats HP with the modularity, and the Tek SD-24 sampling plug-in got "Best in Show", so to speak, from Jim Andrews of Picosecond Pulse Labs (acquired by Tek/Danaher in 2014).My $0.02.Jim Ford Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------From: Precaud <jbau@...> Date: 7/11/20 5:53 AM (GMT-08:00) To: TekScopes@groups.io Subject: Re: [TekScopes] My first scope, a Tektronix 11401 with option 2D extended memory and two 11A34 plugins and an 11A33 plugin. It takes a brave person to admit to liking and using an 11k-series scope  :)I have a couple and "like" them in remote-controlled applications, but hands-on operation is a different matter. The digitizer is excellent (if you need 10 bits), I love the large display, and the 11k preamps are superb. I think the entire user interface was designed with remote programming in mind. Even after years of occasional use I can't remember how to do some basic, simple stuff from the front panel. Because of this, it has earned a spot on the floor next to the bench, deployed only when needed.


Re: FG 504 function generator odd behaviour

Dave Daniel
 

Ir you end up having to replace any of the TO-3 pass transistors in the chassis, be aware that many (all?) new ones may have a different pinout than the originals.

Just something to be aware of.

DaveD

On Jul 11, 2020, at 17:22, Andy Warner <andyw@...> wrote:

On the FG504, the -25V rail is referenced off the +25V one.
Check for bad tantalums on the -25V rail and also independently check the
pass transistor used by that rail, it is in the chassis, not the module.

I have to work on the sweep section of my FG504, which looks like it will
be a right pain. Anyone got any tips for working on the middle board in
this unit ?

On Sat, Jul 11, 2020 at 13:09 Harvey White <madyn@...> wrote:

Generic steps:

turn scope off, wait 5 minutes or so, turn scope on. See if -25 is good
(something could have latched up).

with power off, check continuity of fuses or with power on, check for
very low voltage drop across the fuse. There must always be a voltage
drop because the fuse acts like a resistor.

Look at the bulk supply for the -25. Check against voltage readings on
the schematic. Go through regulator circuit to output and see what
doesn't match. Any transistor where the base-emitter voltage is the
wrong polarity indicates transistor is off. Any transistor (except a
darlington) where the B-E voltage exceeds 0.7 volts is likely bad.

Typical things to fail: pass transistor.

in the event of a short circuit, check the current sense resistor (the
low value one from the pass transistor to the output) and then check the
(frequently done like this) transistor which has the base/emitter
junction connected across the resistor. Too much current and the
transistor turns on, stealing base drive from the pass transistor, and
turning it off. Current limiting.

In many tek supplies, the - supply is a positive supply in topology,
with what would be the ground being the negative lead, and what you'd
think ought to be the positive output grounded. The voltage across the
pass transistor is the difference between the bulk supply and the
desired voltage.

Check also to see what the reference voltage is for the -25 volt
supply. It must be exact, otherwise the supply will be off.

Harvey


On 7/11/2020 1:56 PM, Colin Herbert via groups.io wrote:
Oops! I have checked the voltages and while the +25V (+24.99), +15V
(+14.98)
and -15V (-14.98) are just about bang on, the -25V is sitting at -3.58V.
I
really can't remember if this was the case when I checked previously,
but it
is now. I did manage to short something out with the DMM probes, so that
may
have given this problem, but sure as sure it needs to be fixed, but how?
Colin.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Dave
Daniel
Sent: 10 July 2020 18:13
To: TekScopes@groups.io
Subject: Re: [TekScopes] FG 504 function generator odd behaviour

The first thing to do is measure the power rails to make sure that the
voltages are in spec and clean.

DaveD

On Jul 10, 2020, at 13:04, Colin Herbert via groups.io
<colingherbert=blueyonder.co.uk@groups.io> wrote:
I have an FG 504 which is showing some odd behaviour. The triangle-wave
shows asymmetry in that the negative peaks of the wave are rounded-off at
any frequency and the positive ones have a similar but lesser problem at
higher frequencies. This also seems to manifest itself as what looks like
cut-off on the negative peaks of the sine-wave and lesser cut-off on
positive peaks. While the triangle-waves are more-or-less symmetrical,
the
sine-waves are definitely not so, showing a nearly three-to-one voltage
ratio in favour of positive peaks. There is also noticeably overshoot on
the
square-waves at anything above 1kHz and only a DC offset at frequencies
below 80Hz.
I am totally ignorant of how this function generator produces
triangle-waves, but I do understand that the square-waves and sine-waves
are
derived from the triangle-wave. Does anyone have any help that they can
offer? I would be grateful to get this useful function-generator working
properly.
Colin.









--
Andy



Re: Tektronix 2230

satbeginner
 

Hi,

That's why I suggested to look in old equipment as well

Sometimes it's inside an old laptop PS you can crack open, or behind the screen of a broken tablet.

It's a very small transformer, so only little is needed.


Re: Tektronix 2230

Jim Ford
 

Be aware it's not cheap; I remember paying about $30 for a roll.   I use it sparingly.  It drives me nuts when people at work use it to wrap packages and such!Jim Ford Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------From: Raymond Cote <@Bluegrass> Date: 7/11/20 2:02 AM (GMT-08:00) To: TekScopes@groups.io Subject: Re: [TekScopes] Tektronix 2230 Digikey lists it as available in tape form. YMMV In matters of style, float with the current. In matters of Principle, stand like a rock. “.   —  Thomas Jefferson —> On Jul 11, 2020, at 02:54, Saroj Pradhan <sarojman.Pradhan@...> wrote:> > > >> On Sat, Jul 11, 2020, 1:04 PM satbeginner <@satbeginner> wrote:>> >> Hello Saroj,>> >> Many moons ago in the lab I worked we had a guy who made all the special>> use transformers we needed.>> >> I learned from him to use what he used :-)>> >> In between windings he used a thin layer of Kaptan foil (polyimide,  thin>> light brown, slightly transparent) held in place with a simple piece of>> normal electrical tape.>> Then the next winding, insulation layer, next winding, etc.>> >> This kaptan is heat resistant, thin and also provide s good isolation.>> >> Sometimes you find it as a foil used in old electrical devices,and you>> only need a little.>> >> Good luck,>> >> Leo>> >> >> >> > > >


Tektronix TM500/TM5000 extender version 1.0

Ke-Fong Lin
 

Hi everyone,

I've a small TM500/TM5000 extender project and it is basically completed.
It's been tested working as an extender.
It's been also tested working as a standalone debugging device. That is to power a plug-in from lab supplies, which can be useful for repair.
Everything is now on github:

https://github.com/anotherlin/tek_tm_ext

Can you guys have a look and tell me if you can make any sense of it?
It's basically the same as version 0.8, without the bodge wire needed:
https://groups.io/g/TekScopes/album?id=243643

I'll add some photos for reference on the github tomorrow, otherwise it may be a bit abstract.

The standalone AC supplies have not been tested, but I'm pretty confident. It's basically some wiring.
The power good (TM5000 PWR pin) circuitry neither because both my SG5010 and AA5001 ignore it
But it's also very simple, so it should work.

Best regards,


Re: Tektronix Blue paint

Richard Knoppow
 

Its better. The example I used in my post does not really have columns. I found that part of the preservation of formatting depends on the choice of font. If you use variable spacing and the reader uses fixed spacing things will not line up. I don't know a real cure for this.
   I suppose someone who mixes custom paints probably understands the formula.

On 7/11/2020 2:06 PM, Reed Dickinson wrote:
I am re-sending the data as the columns did not line up.    Years ago a friend, Stan Griffiths, now deceased, passed on to me this Tektronix Blue paint formula.  He called it Williamsburg Blue.  He said it came from a commercial paint company but I really do not know how to read the formula.  Here it is:
B  4Y22  Black,    C 33 Yellow oxide,  D 1Y29 Green,  W 1Y32 White, E 1Y45 Blue, Base 7-916Y = ounces, 4Y = 4 ounces,  48 Points = 1 ounce
Another formula, this one from the late Dean Kidd, is as follows:
Base, E480 DBD Interior Satin
Lamp Black  37 shots,  Thalo Green  22 half shots,  Thalo Blue 30 half shots, white 1 ounce 8 shots
I would appreciate any feedback on these two formulas for my notes.
Reed Dickinson, 1705 Stonehenge Drive, Tustin, CA  92780, reed714@...




--
Richard Knoppow
dickburk@...
WB6KBL


Re: FG 504 function generator odd behaviour

Andy Warner
 

On the FG504, the -25V rail is referenced off the +25V one.
Check for bad tantalums on the -25V rail and also independently check the
pass transistor used by that rail, it is in the chassis, not the module.

I have to work on the sweep section of my FG504, which looks like it will
be a right pain. Anyone got any tips for working on the middle board in
this unit ?

On Sat, Jul 11, 2020 at 13:09 Harvey White <madyn@...> wrote:

Generic steps:

turn scope off, wait 5 minutes or so, turn scope on. See if -25 is good
(something could have latched up).

with power off, check continuity of fuses or with power on, check for
very low voltage drop across the fuse. There must always be a voltage
drop because the fuse acts like a resistor.

Look at the bulk supply for the -25. Check against voltage readings on
the schematic. Go through regulator circuit to output and see what
doesn't match. Any transistor where the base-emitter voltage is the
wrong polarity indicates transistor is off. Any transistor (except a
darlington) where the B-E voltage exceeds 0.7 volts is likely bad.

Typical things to fail: pass transistor.

in the event of a short circuit, check the current sense resistor (the
low value one from the pass transistor to the output) and then check the
(frequently done like this) transistor which has the base/emitter
junction connected across the resistor. Too much current and the
transistor turns on, stealing base drive from the pass transistor, and
turning it off. Current limiting.

In many tek supplies, the - supply is a positive supply in topology,
with what would be the ground being the negative lead, and what you'd
think ought to be the positive output grounded. The voltage across the
pass transistor is the difference between the bulk supply and the
desired voltage.

Check also to see what the reference voltage is for the -25 volt
supply. It must be exact, otherwise the supply will be off.

Harvey


On 7/11/2020 1:56 PM, Colin Herbert via groups.io wrote:
Oops! I have checked the voltages and while the +25V (+24.99), +15V
(+14.98)
and -15V (-14.98) are just about bang on, the -25V is sitting at -3.58V.
I
really can't remember if this was the case when I checked previously,
but it
is now. I did manage to short something out with the DMM probes, so that
may
have given this problem, but sure as sure it needs to be fixed, but how?
Colin.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Dave
Daniel
Sent: 10 July 2020 18:13
To: TekScopes@groups.io
Subject: Re: [TekScopes] FG 504 function generator odd behaviour

The first thing to do is measure the power rails to make sure that the
voltages are in spec and clean.

DaveD

On Jul 10, 2020, at 13:04, Colin Herbert via groups.io
<colingherbert=blueyonder.co.uk@groups.io> wrote:
I have an FG 504 which is showing some odd behaviour. The triangle-wave
shows asymmetry in that the negative peaks of the wave are rounded-off at
any frequency and the positive ones have a similar but lesser problem at
higher frequencies. This also seems to manifest itself as what looks like
cut-off on the negative peaks of the sine-wave and lesser cut-off on
positive peaks. While the triangle-waves are more-or-less symmetrical,
the
sine-waves are definitely not so, showing a nearly three-to-one voltage
ratio in favour of positive peaks. There is also noticeably overshoot on
the
square-waves at anything above 1kHz and only a DC offset at frequencies
below 80Hz.
I am totally ignorant of how this function generator produces
triangle-waves, but I do understand that the square-waves and sine-waves
are
derived from the triangle-wave. Does anyone have any help that they can
offer? I would be grateful to get this useful function-generator working
properly.
Colin.









--
Andy


Re: Tektronix Blue paint

Richard Knoppow
 

The formatting is lost on my machine. perhaps you can send it they way I send photographic formulas. Example below.

Kodak D-76
Water (at 125F or 52C).................750.0 mL
Metol....................................2.0 grams
Sodium Sulfite, desiccated.............100.0 grams
Hydroquinon..............................5.0 grams
Borax, granular..........................2.0 grams
Water to make............................1.0 Liter

I think this will stay pretty much intact.

On 7/11/2020 1:44 PM, Reed Dickinson wrote:
Years ago a friend, Stan Griffiths, now deceased, passed on to me this Tektronix Blue paint formula.  He called it Williamsburg Blue.  He said it came from a commercial paint company but I really do not know how to read the formula.  Here it is:
B        4Y22        BlackC        33            Yellow oxideD        1Y29        GreenW        1Y32        WhiteE         1Y45        Blue
Y = ounces4Y = 4 ounces48 Points = 1 ounce
Another formula, this one from the late Dean Kidd, is as follows:
Base, E480 DBD Interior Satin                                  Shots        Half shots
Lamp Black                37Thalo Green                22            1Thalo Blue                   30            1White             1 Oz      8
I would appreciate any feedback on these two formulas for my notes.
Reed Dickinson1705 Stonehenge DriveTustin, CA  92780reed714@...
--
Richard Knoppow
dickburk@...
WB6KBL


Re: Tektronix Blue paint

Reed Dickinson
 

I am re-sending the data as the columns did not line up.    Years ago a friend, Stan Griffiths, now deceased, passed on to me this Tektronix Blue paint formula.  He called it Williamsburg Blue.  He said it came from a commercial paint company but I really do not know how to read the formula.  Here it is:
B  4Y22  Black,    C 33 Yellow oxide,  D 1Y29 Green,  W 1Y32 White, E 1Y45 Blue, Base 7-916Y = ounces, 4Y = 4 ounces,  48 Points = 1 ounce
Another formula, this one from the late Dean Kidd, is as follows:
Base, E480 DBD Interior Satin                                  
Lamp Black  37 shots,  Thalo Green  22 half shots,  Thalo Blue 30 half shots, white 1 ounce 8 shots                  
I would appreciate any feedback on these two formulas for my notes.
Reed Dickinson, 1705 Stonehenge Drive, Tustin, CA  92780, reed714@...


Re: Tek 465 Turns on, No Dot, No Trace

Stephen
 

On Sat, Jul 11, 2020 at 09:05 AM, Tom Miller wrote:


Ok, that sounds like the main problem. That HV multiplier is also used
in the 475 scope as well as the A and B versions. You might check with Q
service in Greece ( excellent to deal with) or search the part number
152-0552-00.  Here is one on ebay. https://www.ebay.com/p/1501921351 but
a bit expensive.

Another option is to build one from parts - it's a cockcroff-walton
multiplier. Should be some info in the archives on groups.io. It is a
tripler so three caps and three diodes plus a 1-3 meg carbon comp
resistor and a case to put it in. Pot with wax.

Ask on the group if anyone has a spare.

Regards

Hmmm... Does it have to be a carbon comp resistor?
I may try to build one using the existing enclosure. I hope it’s not dipped in epoxy.
Dinos at Q-Service is out of this part.
He’s really a very nice guy. I’ve dealt with him a few time, and talked to him on the phone last week.

Maybe I can just replace the parts inside. But I have the feeling it’s not gonna be that easy...
Plus, replacing that part apparently requires removing the entire board, which is a project in itself.
Grrrr...

PS: Were those cracklings sounds i heard to be expected? That startled me. I hope nothing was damaged...


Tektronix Blue paint

Reed Dickinson
 

Years ago a friend, Stan Griffiths, now deceased, passed on to me this Tektronix Blue paint formula.  He called it Williamsburg Blue.  He said it came from a commercial paint company but I really do not know how to read the formula.  Here it is:
B        4Y22        BlackC        33            Yellow oxideD        1Y29        GreenW        1Y32        WhiteE         1Y45        Blue
Y = ounces4Y = 4 ounces48 Points = 1 ounce
Another formula, this one from the late Dean Kidd, is as follows:
Base, E480 DBD Interior Satin                                  Shots        Half shots
Lamp Black                37Thalo Green                22            1Thalo Blue                   30            1White             1 Oz      8      
I would appreciate any feedback on these two formulas for my notes.
Reed Dickinson1705 Stonehenge DriveTustin, CA  92780reed714@...


Re: Tek 465 Turns on, No Dot, No Trace

 

Ok, that sounds like the main problem. That HV multiplier is also used in the 475 scope as well as the A and B versions. You might check with Q service in Greece ( excellent to deal with) or search the part number 152-0552-00.  Here is one on ebay. https://www.ebay.com/p/1501921351 but a bit expensive.

Another option is to build one from parts - it's a cockcroff-walton multiplier. Should be some info in the archives on groups.io. It is a tripler so three caps and three diodes plus a 1-3 meg carbon comp resistor and a case to put it in. Pot with wax.

Ask on the group if anyone has a spare.

Regards

On 7/11/2020 2:24 PM, Stephen wrote:
On Sat, Jul 11, 2020 at 06:24 AM, Tom Miller wrote:

There is a wire jumper at board location A-5 that provides the ground to
the HV multiplier. (note that I am going from old memory so take with a
grain of salt). Measure to ground to see if it is grounded. It is next
to a mounting screw for the multi module. Just lift one end and see if
the HV osc comes up.

If the HV osc is not running, all the CRT vltage readings will be off.

Regards
Ok, so I did lift that jumper. GOOD MEMORY BTW!!! A-5 it was!! Remind me NOT to ever play Naval BattleS with you!

The CRT came to life. I had something when playing With the Intensity and pushing the Beam Finder. But at the same time I did this, I heard some weird cracklings noises coming from the HV area, and a funny smell. Nothing caught fire though. I turn everything down and released the B Finder. Then I turned it off.
What say you? Is this good or bad? What are my options?

Best Regards

--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus


Re: Cleaning TM500 module pushbutton switches

Roy Thistle
 

On Sat, Jul 11, 2020 at 08:20 AM, J Mcvein wrote:


it changed to petroleum
according to the filings, they are using hydro-treated spent lubricating oil.
fish oil is more valuable for making axle grease... a.k.a. as margarine.
Ya... don't use margarine to lube your TM500 module push-button switches.


Re: Cleaning TM500 module pushbutton switches

Roy Thistle
 

On Fri, Jul 10, 2020 at 06:18 PM, Greg Muir wrote:


wondering if WD40 Company has changed the formulation
The liquid stuff, in the gallon cans, in CONUS, is "different", from the spray, in a way that may explain your observations.
Too much chemistry, in one's posts, makes one unpopular...
But... "petroleum oils" oxidize, change colour, and become more viscous, in humid, and acidic (Hawaiian ocean air?) environments over sufficient time.
The spray imparts only a thin layer of "petroleum oil" ... and most of that drips off, along with the solvent. The little that remains... well...sunlight, heat, dust, and even microbes, they soon diminish that.
The oxidation of the thicker layer of "petroleum oil" applied... by using {heavy coatings} of the the liquid stuff, in the gallon cans could... at least partly explain what you observed.
Ya... don't use the liquid stuff, in the gallon cans, to dip your TM500 module push-button switches.


Re: 7904

Bill Riches
 

Hmmm.  I guess I can't save links with dropbox.  Any suggestions?
Bill

On Saturday, July 11, 2020, 03:10:29 PM EDT, Bill Riches via groups.io <bill.riches=verizon.net@groups.io> wrote:

Here are some trace shots - sense tp low volt reg and reg board.
Looks like-50 and -5 looks bad on the low volt reg board.  Any suggestions?
In a good power supply will it power up with not being connected to main frame or go into burst mode due to no load?

Trusty 465 used - first tek I purchased in 1980.  Still going strong!
73,
Bill, WA2DVUCape May609 425 8651
7904 ps sense test point LV reg board


|
|
|
|  |  |

|

|
|
|  |
7904 ps sense test point LV reg board

Shared with Dropbox
|

|

|

7904 Rectifier board


|
|
|
|  |  |

|

|
|
|  |
7904 Rectifier board

Shared with Dropbox
|

|

|


7904

Bill Riches
 

Here are some trace shots - sense tp low volt reg and reg board.
Looks like-50 and -5 looks bad on the low volt reg board.  Any suggestions?
In a good power supply will it power up with not being connected to main frame or go into burst mode due to no load?

Trusty 465 used - first tek I purchased in 1980.  Still going strong!
73,
Bill, WA2DVUCape May609 425 8651
7904 ps sense test point LV reg board


|
|
|
| | |

|

|
|
| |
7904 ps sense test point LV reg board

Shared with Dropbox
|

|

|

7904 Rectifier board


|
|
|
| | |

|

|
|
| |
7904 Rectifier board

Shared with Dropbox
|

|

|


Re: Looking for

stevenhorii
 

Dave,
Yes, you are correct. Out of curiosity, I looked up Grass Valley and they
became part of Belden but now they are part of Black Dragon. I had a video
distribution amplifier made by Grass Valley.

Steve

On Sat, Jul 11, 2020 at 2:59 PM Dave Seiter <d.seiter@...> wrote:

I *think* it was the other way round- Grass Valley group spun off from
Tek.
-Dave
On Saturday, July 11, 2020, 09:32:58 AM PDT, stevenhorii <
sonodocsch@...> wrote:


I have several older Tek NTSC video test items. I had a 1910 digital
generator that was useful in the days of SDTV. If I am not mistaken, Tek
acquired Grass Valley. Group. They made (make, I think) broadcast video
equipment. The Tek test signal generators, waveform monitors, vector
scopes, sync generators, etc. were made by Tek.

Steve H.

On Sat, Jul 11, 2020 at 11:27 Kurt Swanson <kurt2135@...>
wrote:

I have a 7J20. Unfortunately, I don't have the sampling head. I've had
it for a long time, and when I got it, I knew it was uncommon, but I
figured a sampling head would eventually turn up. No such luck - at
least
so far.
I got it wanting to do some optical spectroscopy work, and still would
like to get it working for that purpose.

If anyone has a sampling head, let me know, otherwise I might reluctantly
let this one go for sale or trade (and I do mean reluctantly).

Regards - Kurt








Re: Looking for

Dave Seiter
 

I *think* it was the other way round- Grass Valley group spun off from Tek.
-Dave

On Saturday, July 11, 2020, 09:32:58 AM PDT, stevenhorii <sonodocsch@...> wrote:


I have several older Tek NTSC video test items. I had a 1910 digital
generator that was useful in the days of SDTV. If I am not mistaken, Tek
acquired Grass Valley. Group. They made (make, I think) broadcast video
equipment. The Tek test signal generators, waveform monitors, vector
scopes, sync generators, etc. were made by Tek.

Steve H.

On Sat, Jul 11, 2020 at 11:27 Kurt Swanson <kurt2135@...> wrote:

I have a 7J20.  Unfortunately, I don't have the sampling head.  I've had
it for a long time, and when I got it, I knew it was uncommon, but I
figured a sampling head would eventually turn up.  No such luck - at least
so far.
I got it wanting to do some optical spectroscopy work, and still would
like to get it working for that purpose.

If anyone has a sampling head, let me know, otherwise I might reluctantly
let this one go for sale or trade (and I do mean reluctantly).

Regards - Kurt




Re: Looking for

Dave Daniel
 

I have a DP-100. It was pretty inexpensive. I remember wondering when I received it what I was going to do with it. I still haven't come up with anything.

DaveD

On 7/11/2020 12:32 PM, stevenhorii wrote:
For those seeking a 7J20/J20 or parts, after the other posts on this, I’ve
decided I won’t continue searching for one other than out of interest of
what the price might be. It would be a novelty for me as I have equipment I
need to do the testing I do.

By the way, there’s an interesting module on eBay:

https://www.ebay.com/itm/1pp-1-qty-tektronix-dp-100-digital-video-probe/264388939882

Apparently a TM500 plug-in (TekWiki) and a pod is shown with it on the
TekWiki page but not by the seller on eBay.

I have several older Tek NTSC video test items. I had a 1910 digital
generator that was useful in the days of SDTV. If I am not mistaken, Tek
acquired Grass Valley. Group. They made (make, I think) broadcast video
equipment. The Tek test signal generators, waveform monitors, vector
scopes, sync generators, etc. were made by Tek.

Steve H.

On Sat, Jul 11, 2020 at 11:27 Kurt Swanson <kurt2135@...> wrote:

I have a 7J20. Unfortunately, I don't have the sampling head. I've had
it for a long time, and when I got it, I knew it was uncommon, but I
figured a sampling head would eventually turn up. No such luck - at least
so far.
I got it wanting to do some optical spectroscopy work, and still would
like to get it working for that purpose.

If anyone has a sampling head, let me know, otherwise I might reluctantly
let this one go for sale or trade (and I do mean reluctantly).

Regards - Kurt



--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus


Re: FG-504 not-so odd behavior

keantoken
 

10*10^2=1KHz, so it seems to be partly working. All functions should be 1KHz so something is off.
Check that the oscillation is coming from the oscillator. The oscillator may be behaving normally and the output amp is oscillating on it's own. If they are both oscillating at 25MHz then I would look at the decoupling caps or a broken ground causing feedback between the output amp and the oscillator.
I would try a little harder to identify the fault in the non functional one. It could be that when you find the problem it will suddenly work fine with no issues. On Saturday, July 11, 2020, 09:51:04 AM CDT, John Ferguson via groups.io <jferg977=aol.com@groups.io> wrote:

with the FG 504 set at start freq 10, stop freq 40, multiplier at 10^2,
sweep off,

measured on my 2445b, Sine freq 982.3 Hz, Sawtooth 975.9 Hz and Square
wave 24.5 mHz.

The square wave is an asymmetrical  sine wave, not the Sawtooth I was
expecting.

Since I have two of these things and this one at least does this, and
also the sweeps and other functions, all except a square wave, and the
other one does nothing, this might be the one to fix.

What do you think?


john