Date   

Re: Further of my Tek 2465A S/N B019121

tom jobe <tomjobe@...>
 

Look at the center of the black plastic cover, there is plastic prong made right in the cover that sticks straight down with a little barb on the end of it.
You push the prong to the side just a little and the cover comes off.
Those two large capacitors are rarely a problem, and most folks would have you leave them alone if the ESR checks out okay.
tom jobe...

On 5/22/2019 2:45 PM, Lawrence Joy via Groups.Io wrote:
To Brad, AA1IP,
I did not use your aluminum foil over the tip of my Torx T-10 suggestion. I asked on my local 2 m net and it was suggested to use an Allen (hex key) wrench. I used a 7/64" size Allen wrench, and a pair of pliers, and was able to get that last screw out. I checked one of the "good" screws and the 7/64" size would not fit, so that particular bad boy screw was deformed.

To everyone,
Now that I have the A2A1--Regulator CCA and the A3--Inverter CCA separated I need to do one more removal. How do you get the black plastic cover off the black plastic bottom that contains the A3C1021 and A3C1022, 290 µF 200 V DC capacitors? The parts layout drawing of the A3 CCA of Figure 10-13 does not show this. The top is loose and I tried a flat blade screwdriver around the sides I could get to but I didn't want to break anything, or is that what I have to do?
Tnx, WN8P, Larry


Further of my Tek 2465A S/N B019121

Lawrence Joy
 

To Brad, AA1IP,
I did not use your aluminum foil over the tip of my Torx T-10 suggestion. I asked on my local 2 m net and it was suggested to use an Allen (hex key) wrench. I used a 7/64" size Allen wrench, and a pair of pliers, and was able to get that last screw out. I checked one of the "good" screws and the 7/64" size would not fit, so that particular bad boy screw was deformed.

To everyone,
Now that I have the A2A1--Regulator CCA and the A3--Inverter CCA separated I need to do one more removal. How do you get the black plastic cover off the black plastic bottom that contains the A3C1021 and A3C1022, 290 µF 200 V DC capacitors? The parts layout drawing of the A3 CCA of Figure 10-13 does not show this. The top is loose and I tried a flat blade screwdriver around the sides I could get to but I didn't want to break anything, or is that what I have to do?
Tnx, WN8P, Larry


Re: OT: App that keeps track of "Or Best Offer" auctions on eBay to tell you what a seller will accept.

Tom Gardner
 

On 22/05/19 19:55, David Berlind wrote:
The results don't just included completed auctions, but also
Buy-It-Now listings that were optionally enabled with the "Make Offer"
button. For those listings, you will never know how much was actually paid
for the item. They only show the Buy-It-Now price. The actual sale price
could have been the Buy-It-Now price, or something less.
Goto watchcount.com and paste the ebay item number into the keywords box.

For example:
https://www.ebay.co.uk/itm/Datron-1061A-multimeter-6-5-digit-DC-volts-AC-volts-Resistance-current-GPIB/113707651429

Therefore item number 113707651429

shows


Seller:
testelectro <http://www.watchcount.com/go/?seller=testelectro&cid=ilu->[efb <http://www.watchcount.com/go/?cid=ilu-efb-&url=https%3A%2F%2Ffeedback.ebay.co.uk%2Fws%2FeBayISAPI.dll%3FViewFeedback2%26ftab%3DFeedbackAsSeller%26userid%3Dtestelectro>][sld <http://www.watchcount.com/completed.php?bfw=1&bslr=testelectro#serp>]


View Count:
 104
 Watch Count:
3 <http://www.watchcount.com/go/?item=113707651429&cid=ilu->
Start Time:
 Thursday, 04-Apr-19 08:11:44UTC
End Time:
 Friday, 12-Apr-19 13:30:01UTC (40.28 days ago)
Current Bid/Price (GBP):
£ 295.00
Best Offer Enabled
Sold For (GBP):
 £ 270.00(check price here? –>) [History <http://www.watchcount.com/go/?cid=ilu-ihist-113707651429-&url=https%3A%2F%2Foffer.ebay.co.uk%2Fws%2FeBayISAPI.dll%3FViewBidsLogin%26item%3D113707651429>]


Re: OT: App that keeps track of "Or Best Offer" auctions on eBay to tell you what a seller will accept.

David Berlind
 

I think those one of a kind opportunities still exist on eBay. To one of
the points made by Dennis, once I know what I'm looking for across a
variety of marketplaces (eBay, CraigList, the Facebook Marketplace,
ShopGoodWill.com, etc.), the first thing I do is research what that item
has historically sold for on eBay. When you search eBay for an item, you
can filter the search to "Completed Items." (as opposed to active
listings). The results don't just included completed auctions, but also
Buy-It-Now listings that were optionally enabled with the "Make Offer"
button. For those listings, you will never know how much was actually paid
for the item. They only show the Buy-It-Now price. The actual sale price
could have been the Buy-It-Now price, or something less. But, of the
completed auctions where there was actual bidding, you can see what the
winning bids were, and that's what I go by to get some idea of the current
market value of something.

Then, I start to scour all the marketplaces for that item. Sometimes, I end
up buying on eBay. Other times not. The most recent example of this for me
was a B&K 875B LCR meter. My eBay research revealed that they were selling
for $125-$150. I watched all the marketplaces (easier to automate for some
than others). On eBay, I set up an alert to let me know when their were new
listings for that item. Then, as those listings come up, if it's an
auction, I put that actual listing on my eBay watch list (click the "watch"
button on the listing). As the auction gets closer to ending, eBay will
send you notifications that it's almost over. Yesterday, after getting a
notification and as the auction was minutes away from closing, .... I had
it open .. and got the item for $64 (shipping included)

https://www.ebay.com/itm/B-K-Model-875B-LCR-Meter-with-test-leads-and-manual/113745581598

I followed this same technique with the Tek signal standardizer plug in
that I just bought a couple of weeks ago off eBay for calibrating my 7000
series scopes (acquired for $77.. including shipping).

If there's insufficient historical data, and you're patient, another trick
is to wait for one to come up for auction, and just watch it all the way to
the end to see what it sells for a couple of times. I put this exact
technique to use today for a nearly new Atomos Ninja V external video
monitor that sold for $594 with shipping. Now I know what the most I should
pay is.

https://www.ebay.com/itm/Atomos-Ninja-V-5-4K-HDMI-Recording-Monitor-SSD-Battery-HDMI-Cable-Mint-/323812493375

For Craigslist, you can use Google Alerts to notify you when the item comes
up for sale anywhere in the country. Just use "craigslist.org" as the
target domain in the Google Alert search string.

OK, hope this helps.

On Wed, May 22, 2019 at 2:04 PM Dennis Tillman W7PF <dennis@ridesoft.com>
wrote:

There are certainly a lot of people asking me to let them know if I ever
find it again. I remember using all the strategies you describe when eBay
was a lot less controlling of their own auctions. Everything you can learn
about a seller, the price an item sells at, and other bidders behavior
rpatterns is knowledge you can use to improve your odds of winning an
auction. eBay has gradually caught on to this and has steadily placed
restrictions on every bit of information that can be used to give you an
edge.

You have seen the very same thing happening. I think I was very lucky to
have been so active on eBay so many years ago. At the time I never realized
that it wouldn't always be that way. This is unfortunate, but it explains
why I turn to eBay for different things now than I did before. Gone are the
exciting one of a kind items you can sometimes get for a ridiculous price
because your put in a bid early and the sniping site had a meltdown moments
before the auction ended and didn’t place any snipes. I remember a few
times when I won something for the opening bid price that way.

Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of
tekscopegroup@miwww.com
Sent: Wednesday, May 22, 2019 10:04 AM
Subject: Re: [TekScopes] OT: App that keeps track of "Or Best Offer"
auctions on eBay to tell you what a seller will accept.

Back a few years before ebay started to obfuscate all the information on
bidders and sellers an app like that would still have been possible to work
on the public information that was available on any ebay member. Back then
I was even doing myself some manual background checks on other bidders I
was competing with for an item. I used to check on their previous bids
history what items they won/lost etc to try and find patterns, and also how
they liked to send in their highest bid (some people like to send even
amounts, others like weird patterns, like $12.34 or $111.11 and so on) to
try to anticipate their next maximum bid. Also back then if you managed to
get in your bid in the last 10-15 seconds before the end you usually won if
your bid was high enough, and I was quite successful (inc synchronizing the
PC clock with ebay clock, make sure to be freshly logged in, etc). I even
had friends asking me to snag something of ebay for them. But nowadays they
even automated sniping and sometimes you get beaten by a bid sent 1-2
seconds before the auction ends. Anyway gathering relevant information on
other bidders or sellers is now for the most part no longer possible as it
used to be. So unless this app has a way to sneak into ebay's servers and
bypass whatever security they have in place to protect their databases I
don't see how an app like that is still possible. Unless someone found a
backdoor.




--
Dennis Tillman W7PF
TekScopes Moderator




Re: OT: App that keeps track of "Or Best Offer" auctions on eBay to tell you what a seller will accept.

radioconnection@...
 

At one time eBay posted the sale price for an accepted best offer. I think they changed that, at least in the US listings.

I am not sure how a program can predict what a seller will accept since that info is no longer shown?


Re: Old Tektronix Books

ROLYNN PRECHTL K7DFW
 

The "Typical Oscilloscope Circuitry" book. Rolynn said it was at w140 ("TekWiki"), but I couldn't find it so I asked him where it was in the w140 site.

===========================================================================================

Not even close.

Rolynn said that the:

1961 publication eliminates some.
(1961 publication date eliminates some of the scopes from where the schematics came from)

The power supply might be a 531/535/541 but I'm not going to spend any time with this since the manuals are on TekWiki.

(the manuals for the potential scope candidates are on TekWiki and to do your own detective work to find out which instrument schematics are in the book)

Clear as a bell - to me.

Rolynn


Re: OT: App that keeps track of "Or Best Offer" auctions on eBay to tell you what a seller will accept.

 

There are certainly a lot of people asking me to let them know if I ever find it again. I remember using all the strategies you describe when eBay was a lot less controlling of their own auctions. Everything you can learn about a seller, the price an item sells at, and other bidders behavior rpatterns is knowledge you can use to improve your odds of winning an auction. eBay has gradually caught on to this and has steadily placed restrictions on every bit of information that can be used to give you an edge.

You have seen the very same thing happening. I think I was very lucky to have been so active on eBay so many years ago. At the time I never realized that it wouldn't always be that way. This is unfortunate, but it explains why I turn to eBay for different things now than I did before. Gone are the exciting one of a kind items you can sometimes get for a ridiculous price because your put in a bid early and the sniping site had a meltdown moments before the auction ended and didn’t place any snipes. I remember a few times when I won something for the opening bid price that way.

Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of tekscopegroup@miwww.com
Sent: Wednesday, May 22, 2019 10:04 AM
Subject: Re: [TekScopes] OT: App that keeps track of "Or Best Offer" auctions on eBay to tell you what a seller will accept.

Back a few years before ebay started to obfuscate all the information on bidders and sellers an app like that would still have been possible to work on the public information that was available on any ebay member. Back then I was even doing myself some manual background checks on other bidders I was competing with for an item. I used to check on their previous bids history what items they won/lost etc to try and find patterns, and also how they liked to send in their highest bid (some people like to send even amounts, others like weird patterns, like $12.34 or $111.11 and so on) to try to anticipate their next maximum bid. Also back then if you managed to get in your bid in the last 10-15 seconds before the end you usually won if your bid was high enough, and I was quite successful (inc synchronizing the PC clock with ebay clock, make sure to be freshly logged in, etc). I even had friends asking me to snag something of ebay for them. But nowadays they even automated sniping and sometimes you get beaten by a bid sent 1-2 seconds before the auction ends. Anyway gathering relevant information on other bidders or sellers is now for the most part no longer possible as it used to be. So unless this app has a way to sneak into ebay's servers and bypass whatever security they have in place to protect their databases I don't see how an app like that is still possible. Unless someone found a backdoor.




--
Dennis Tillman W7PF
TekScopes Moderator


Re: Latest firmware for TDS210 and TDS2CM?

 

On Wed, May 22, 2019 at 06:56 AM, Jared Cabot wrote:


I have an old TDS210 scope with TDS2CM comms/math module and I was wondering
if anyone knows what the latest firmware revisions for these modules is,
If you by old mean the first generation that had BNC connectors with two pins and F/W in a removable 24C040 PROM the last version as far
as I know is 1.19. The next generation had BNC connetors with four pins and F/W in flash ROM. They were programmed by attaching a
special programming fixture into the I/O module compartment. I don't know the latest version for those.
F/W is the same for TDS210 and TDS220.
/Håkan


Re: OT: App that keeps track of "Or Best Offer" auctions on eBay to tell you what a seller will accept.

tekscopegroup@...
 

Back a few years before ebay started to obfuscate all the information on bidders and sellers an app like that would still have been possible to work on the public information that was available on any ebay member. Back then I was even doing myself some manual background checks on other bidders I was competing with for an item. I used to check on their previous bids history what items they won/lost etc to try and find patterns, and also how they liked to send in their highest bid (some people like to send even amounts, others like weird patterns, like $12.34 or $111.11 and so on) to try to anticipate their next maximum bid. Also back then if you managed to get in your bid in the last 10-15 seconds before the end you usually won if your bid was high enough, and I was quite successful (inc synchronizing the PC clock with ebay clock, make sure to be freshly logged in, etc). I even had friends asking me to snag something of ebay for them. But nowadays they even automated sniping and sometimes you get beaten by a bid sent 1-2 seconds before the auction ends. Anyway gathering relevant information on other bidders or sellers is now for the most part no longer possible as it used to be. So unless this app has a way to sneak into ebay's servers and bypass whatever security they have in place to protect their databases I don't see how an app like that is still possible. Unless someone found a backdoor...


Re: Old Tektronix Books

Dave Daniel
 

Thanks for clarifying that.

I thought there was copy on the TekWiki as well. When I saw that there wasn’t, I went to upload my copy. It was at that point that I discovered that (a) I don’t seem to have a copy and (2) I could not find a copy online.

I still think I had a PDF copy at one time.

FaveD

Sent from a small flat thingy

On May 22, 2019, at 12:09, Dave Wise <david_wise@phoenix.com> wrote:

The "Typical Oscilloscope Circuitry" book. Rolynn said it was at w140 ("TekWiki"), but I couldn't find it so I asked him where it was in the w140 site.

Dave Wise
________________________________________
From: TekScopes@groups.io <TekScopes@groups.io> on behalf of Dave Daniel <kc0wjn@gmail.com>
Sent: Tuesday, May 21, 2019 5:54 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Old Tektronix Books

Where what?

DaveD

Sent from a small flat thingy

On May 21, 2019, at 20:26, Dave Wise <david_wise@phoenix.com> wrote:

Where? I found the Concepts series, but Typical Oscilloscope Circuitry is not a Concepts book.

Thanks,
Dave Wise
________________________________________
From: TekScopes@groups.io <TekScopes@groups.io> on behalf of ROLYNN PRECHTL K7DFW <k7dfw@clatskanie.com>
Sent: Tuesday, May 21, 2019 1:15 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Old Tektronix Books

I wonder what scope the schematic examples are taken from. They certainly look genuine.
========================================================================


1961 publication eliminates some.

The power supply might be a 531/535/541 but I'm not going to spend any time with this since the manuals are on TekWiki.



Rolynn











Re: Old Tektronix Books

Dave Wise
 

The "Typical Oscilloscope Circuitry" book. Rolynn said it was at w140 ("TekWiki"), but I couldn't find it so I asked him where it was in the w140 site.

Dave Wise
________________________________________
From: TekScopes@groups.io <TekScopes@groups.io> on behalf of Dave Daniel <kc0wjn@gmail.com>
Sent: Tuesday, May 21, 2019 5:54 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Old Tektronix Books

Where what?

DaveD

Sent from a small flat thingy

On May 21, 2019, at 20:26, Dave Wise <david_wise@phoenix.com> wrote:

Where? I found the Concepts series, but Typical Oscilloscope Circuitry is not a Concepts book.

Thanks,
Dave Wise
________________________________________
From: TekScopes@groups.io <TekScopes@groups.io> on behalf of ROLYNN PRECHTL K7DFW <k7dfw@clatskanie.com>
Sent: Tuesday, May 21, 2019 1:15 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Old Tektronix Books

I wonder what scope the schematic examples are taken from. They certainly look genuine.
========================================================================


1961 publication eliminates some.

The power supply might be a 531/535/541 but I'm not going to spend any time with this since the manuals are on TekWiki.



Rolynn





Re: 7B92A time-base plug-in odd behaviour

Roger Evans
 

On my 7B92A, the microswitch near the front panel is connected by a single wire to P911 on the interface board. P911 is to be found on schematic <4>, 'Delaying Sweep', near the top right corner. It is marked as going to R334 on schematic <3> and the switch is marked as S490. S800 on 'Horizontal Logic', schematic <7> is marked with 'pull for alt, push for delay' and is surely the second switch on that shaft, it connects through to the Readout board.

I noticed while investigating my 7B92A that the whte plastic 'cotton reel' that activates the microswitch didn't seem to be an entirely tight fit on the shaft but settled down happily after a few iterations. I hadn't noticed any odd behaviour when it is operating in the mainframe.

Regards,

Roger


Re: 7B92A time-base plug-in odd behaviour

Albert Otten
 

Hi Colin,

S490 is shown at diagram <4> top-right (in my manual Rev. D, April 1976). Switching contact goes to GND, one choice is open, the other(LOCKED) connects it to P911 at/to the A6 Interface Board. From there also to R334 at <3>. Somewhat vague, as if R334 is in the wire , then to P936 and P204. I didn't look at the function (yet).

Albert

On Wed, May 22, 2019 at 02:10 PM, Colin Herbert wrote:


I have a 7B92A which is puzzling me. When turned on, it will only show the
"ALT" time-base, which isn't altered by the time-base Time/Div knob, but after
warming-up for probably only a minute or so, everything seems to work
correctly. I have a feeling that this is associated with one or other of the
switches on the "Pull for Alt / Push for Dly'd" switch. I am a bit puzzled
about these two switches and the Service Manual isn't enlightening me too
well. There is a micro-switch close to the front-panel, which I _think_ is
S490 (the mechanical parts list refers to it as "SWITCH, SENS:(SEE S490
REPL)). This only operates when the "Time/Div or Dly Time" knob is pulled out
with the two time-bases locked. It then stays in that position until the
delaying and delayed time-bases are at the same Time/Div again and the knob
pushed in. It seems to be connecting something to chassis ground when the knob
is pushed in, but I can't locate it anywhere in the manual. The other switch
that is operated by pulling/pushing the time-base knob looks to be a
slider-switch on the Readout board, but it is on the inner face of this board
and difficult to see without removing the board. I can't find out what it
does, as I can't locate it in the manual.
Can anyone enlighten me as to the identity of these two switches and their
function? Also, some idea as to what might be causing the odd behaviour before
the time-base plug-in warms up?
TIA, Colin.


7B92A time-base plug-in odd behaviour

Colin Herbert
 

I have a 7B92A which is puzzling me. When turned on, it will only show the "ALT" time-base, which isn't altered by the time-base Time/Div knob, but after warming-up for probably only a minute or so, everything seems to work correctly. I have a feeling that this is associated with one or other of the switches on the "Pull for Alt / Push for Dly'd" switch. I am a bit puzzled about these two switches and the Service Manual isn't enlightening me too well. There is a micro-switch close to the front-panel, which I _think_ is S490 (the mechanical parts list refers to it as "SWITCH, SENS:(SEE S490 REPL)). This only operates when the "Time/Div or Dly Time" knob is pulled out with the two time-bases locked. It then stays in that position until the delaying and delayed time-bases are at the same Time/Div again and the knob pushed in. It seems to be connecting something to chassis ground when the knob is pushed in, but I can't locate it anywhere in the manual. The other switch that is operated by pulling/pushing the time-base knob looks to be a slider-switch on the Readout board, but it is on the inner face of this board and difficult to see without removing the board. I can't find out what it does, as I can't locate it in the manual.
Can anyone enlighten me as to the identity of these two switches and their function? Also, some idea as to what might be causing the odd behaviour before the time-base plug-in warms up?
TIA, Colin.


Re: Spectrum Analyzers

John Miles
 

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Gary
Robert Bosworth
Sent: Tuesday, May 21, 2019 7:11 PM
To: TekScopes@groups.io
Subject: [TekScopes] Spectrum Analyzers

Does anyone know the exact differences between a Tektronix 495P Spectrum
Analyzer and a 496P Spectrum Analyzer? They have the same input frequency
range, but apparently have a completely different front control panel.
The front panels aren't actually *that* different, but they are pretty different beasts under the skin. They are both 1.8 GHz models, but the 496 was the second model in the product line, released in the late 1970s/early 1980s timeframe after the original 492 came out. (The first 496s were sold as 492s with option 6, in fact.)

The 495, on the other hand, was one of the last models, produced as late as 1993 or so.

Like the 497 that radioconnection is talking about, there were early versions of the 495 that lacked some of the features like the signal counter that were added to the later-production ones. But the later-production examples with all the bells and whistles and post-B030000 serial numbers will also have capacitor leakage problems that will not be an issue in the earlier ones.

-- john, KE5FX


Latest firmware for TDS210 and TDS2CM?

Jared Cabot
 

Hi,

I have an old TDS210 scope with TDS2CM comms/math module and I was wondering if anyone knows what the latest firmware revisions for these modules is, and if anyone has these firmware files?

I was reading that some changes were made in the later firmwares and I have itchy fingers if my unit is an earlier rev.

Thanks!


Spectrum Analyzers

Gary Robert Bosworth
 

Does anyone know the exact differences between a Tektronix 495P Spectrum Analyzer and a 496P Spectrum Analyzer? They have the same input frequency range, but apparently have a completely different front control panel.


Re: 497P frequency counter question? How to turn on?

radioconnection@...
 

B0202199

Looks like most parts are late 1990 date codes.


Re: 497P frequency counter question? How to turn on?

John Miles
 

What's your serial #? Before B020000, the 497s were derived from the 492A hardware and didn't support the counter feature. If your front panel doesn't have a COUNT button, then that's the case with your unit.

What I'm not sure about offhand is whether the B020000 through B030000 series had counter support. Post-B030000 they definitely did, because those were basically relabeled 494As.

The good news is that while you may not be able to enable the counter with the firmware and/or hardware you have, the 492As were free of the nasty SMT electrolytics and are going to be more reliable as a result despite being a couple years older.

-- john, KE5FX

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of
radioconnection@cox.net
Sent: Tuesday, May 21, 2019 6:25 PM
To: TekScopes@groups.io
Subject: [TekScopes] 497P frequency counter question? How to turn on?

I think the dip switches are set to enable the frequency counter option in 497P,
but I do not have a clue as to how to tell whether it is working or not. What
push button enables the counter on the 497P front panel, and what should I see
when and if the counter is really enabled? I've never seen a function not
defined error while randomly trying to figure out what does what.

Pete


497P frequency counter question? How to turn on?

radioconnection@...
 

I think the dip switches are set to enable the frequency counter option in 497P, but I do not have a clue as to how to tell whether it is working or not. What push button enables the counter on the 497P front panel, and what should I see when and if the counter is really enabled? I've never seen a function not defined error while randomly trying to figure out what does what.

Pete

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