Re: Tek 465b focus issue

DG

Are you able to see two photos I uploaded into the folder named "Tek 465b focus issue"?
One of the pictures shows what the Tek is displaying with the probe on the Signal Generator output.
Another picture shows my functional 20MHz Tenma scope displaying the same signal taken from the BNC connector in the back of the misbehaving Tek.
As my Tech friend explained, the signal at the rear BNC is what feeds the CRT?

Re: Tek 465b focus issue

#15805

开云体育

Ar you sure that it is unfocused? Maybe you have a kind of high frequency oscillation or ripple over the signal. Try to see with the other scope the signal at the deflection plates connections.

El 31/08/2022 a las 19:53, DG escribió:

The trace does not go dimmer with max intensity.?
I included screenshots in my original post but they did not post. I added them to the picture folder that is named the same as my thread title. Can you see them?

Libre de virus.

Updated album Tek 465b focus issue #photo-notice

Group Notification

#15804

DG <grind.fix@...> updated the album Tek 465b focus issue

Re: Tek 465b focus issue

DG

#15803

Yes, adjustment goes through the center but I can't get it as sharp as expected?

Re: Tek 465b focus issue

#15802

I found your pics. The trace is not as sharp as I'd expect from?a fully?functioning Tek scope.?

I think on my scope "Focus" allows for this adjustment, but it sounds like you've tried that.?

Show quoted text

On Wed, Aug 31, 2022 at 12:04 PM DG <grind.fix@...> wrote:

Is there an option to attach photos to the post?

Re: Tek 465b focus issue

DG

#15801

Album name : "Tek 465b focus issue"
By member DG

Re: Tek 465b focus issue

DG

#15800

Is there an option to attach photos to the post?

Re: Tek 465b focus issue

#15799

DG - I can't find that?in the pictures?folders.?

Without seeing your issue, I just want to add that my 453's trace (a scope a few years senior to your 465) is just about as sharp and clearly defined as an LCD, when seen against a dark?background. I've always been extremely impressed with that?given?its relative?age as a tool, and the age when it was built and the technology at the time. It actually exceeds in sharpness?any of my other scopes (Tektronix or HP).?

I never had a 465, but I'd expect excellent performance from its screen.?

Radu.?

Show quoted text

On Wed, Aug 31, 2022 at 10:53 AM DG <grind.fix@...> wrote:

The trace does not go dimmer with max intensity.?
I included screenshots in my original post but they did not post. I added them to the picture folder that is named the same as my thread title. Can you see them?

Re: Tek 465b focus issue

DG

#15798

The trace does not go dimmer with max intensity.?
I included screenshots in my original post but they did not post. I added them to the picture folder that is named the same as my thread title. Can you see them?

Added album Tek 465b focus issue #photo-notice

Group Notification

#15797

DG <grind.fix@...> added the album Tek 465b focus issue

Re: Tek 465b focus issue

#15796

开云体育

If you turn the brightness up fully, does the trace start to go dimmer when fully up?

If so that is an indication of worn out CRT.

I don't think the Tek scopes of that era have an especially sharp trace, but obviously MUCH better than you are suggesting.

Les.

On 8/31/22 17:14, DG wrote:

Show quoted text

Hello,

I'm a new?member here. I'm not a repair professional?but a vintage audio hobbyist and use a scope for?testing amplifiers and other audio gear I restore or build from scratch. Most of the equipment I work on is vacuum tube type.

I got this scope on ebay for not much more than the shipping charge. It is in very good cosmetic shape besides?broken?away?cable?wrap feet.
Initially, I couldn't get a trace out of it but noticed that many push switches do not return to "off" position on their own, so I started with cleaning the controls that are accessible. Some of the switches seem sealed but there were many that are not. After cleaning I was able to get a trace on both channels that responds to sine and square but it is not anywhere sharp as I'd expect it to be. I have a friend, who is a retired TV repairman. He was able to improve the scope sharpness by re-seating some transistors in their sockets but the trace is still fuzzy. It responds to Focus and Astigmatism adjustments but it just doesn't get sharp enough to use the scope for any kind of measurements. He seems to think the issue is CRT itself. I took a scope reading out of the rear BNC connection with my Tenma and it displayed a sharp trace.
Here are the examples. First is 1KHz from signal generator displayed by Tek and second is the same signal displayed by Tenma from Tek's rear BNC port:

I can reduce trace intensity to make it sharper but the trace becomes very difficult to see. Increasing intensity makes the trace?very fuzzy.

Does it look like the CRT is the culprit?

My tech checked Anode and Cathode voltages as well as Grid Bias.

All in specs. Focus adjustment passes through the best possible image in the middle of the control rotation. Any suggestions?

I have a service manual copy but it is not complete. Some pages are missing.

Thanks in advance.

DG

Tek 465b focus issue

[email protected]

#15795

Hello,

I'm a new?member here. I'm not a repair professional?but a vintage audio hobbyist and use a scope for?testing amplifiers and other audio gear I restore or build from scratch. Most of the equipment I work on is vacuum tube type.

I got this scope on ebay for not much more than the shipping charge. It is in very good cosmetic shape besides?broken?away?cable?wrap feet.
Initially, I couldn't get a trace out of it but noticed that many push switches do not return to "off" position on their own, so I started with cleaning the controls that are accessible. Some of the switches seem sealed but there were many that are not. After cleaning I was able to get a trace on both channels that responds to sine and square but it is not anywhere sharp as I'd expect it to be. I have a friend, who is a retired TV repairman. He was able to improve the scope sharpness by re-seating some transistors in their sockets but the trace is still fuzzy. It responds to Focus and Astigmatism adjustments but it just doesn't get sharp enough to use the scope for any kind of measurements. He seems to think the issue is CRT itself. I took a scope reading out of the rear BNC connection with my Tenma and it displayed a sharp trace.
Here are the examples. First is 1KHz from signal generator displayed by Tek and second is the same signal displayed by Tenma from Tek's rear BNC port:

I can reduce trace intensity to make it sharper but the trace becomes very difficult to see. Increasing intensity makes the trace?very fuzzy.

Does it look like the CRT is the culprit?

My tech checked Anode and Cathode voltages as well as Grid Bias.

All in specs. Focus adjustment passes through the best possible image in the middle of the control rotation. Any suggestions?

I have a service manual copy but it is not complete. Some pages are missing.

Thanks in advance.

DG

Re: [TekScopes] FTGH: Tek 1730 WFM Instruction Manual

#15794

On 2022-08-20 1:19 p.m., toby@... wrote:
Hi,
Located in Toronto Canada, free for postage.
PN 070-4474-02
Includes schematics.
This is not the same manual as Tekwiki has, which is 070-7948-05 (SN B070000 and above).
This has been claimed.

--Toby


--Toby

Re: TDS 320 SAVE/RECALL ERROR

#15793

Did you post this question at [email protected]?? I think a lot more people see posts over there than here.

Show quoted text

On Thu, Aug 18, 2022 at 4:00 PM hormann via <hormann=[email protected]> wrote:

Hello,? I'm new to the group and just got a TDS 320 that is displaying a save/recall error when I look in the log.? On startup it shows passed in all areas.? ?The manual doesn't provide much insight and I was hoping someone here might have some advice.?

Thanks,?

Doug

FTGH: Tek 1730 WFM Instruction Manual

#15792

Hi,

Located in Toronto Canada, free for postage.

PN 070-4474-02

Includes schematics.

This is not the same manual as Tekwiki has, which is 070-7948-05 (SN B070000 and above).

--Toby

TDS 320 SAVE/RECALL ERROR

[email protected]

#15791

Hello,? I'm new to the group and just got a TDS 320 that is displaying a save/recall error when I look in the log.? On startup it shows passed in all areas.? ?The manual doesn't provide much insight and I was hoping someone here might have some advice.?

Thanks,?

Doug

Re: TDS 7404 configuration issue after replacing CMOS battery

#15790

The DS1245YP-100 was draining the backup battery excessively, so I removed it from the NVRAM a few days ago and since then it has come back up to 3.3 volts. Thinking that this is a sign that it's time to replace the NVRAM, I searched online for "DS1245YP-100" and among other things, found a link to this EEVBlog article:

The OP said that his DS1245YP-100 had a high standby current drain on the battery, and that there are several other reports of the same problem with this same part. Coincidentally, the date code and lot number of his failed NVRAM are identical to mine(!).

I've ordered a replacement NVRAM from Mouser. I'll report back once I get it installed.

Stan

Re: Replacing readout lamps in Tek 576 curve tracer

#15789

开云体育

The read out lamps are fairly easy to replace however it is a bit fiddly. There are 2 U shaped boards per gray can front and back. These need to be pulled out to get to the bulbs. You do not need to disturb the fiber bundles for this process at all however the wires are on the short side of things.

?

Zen

?

Show quoted text

From: [email protected] <[email protected]> On Behalf Of Stan
Sent: Saturday, July 30, 2022 10:52 PM
To: [email protected]
Subject: [TekScopes2] Replacing readout lamps in Tek 576 curve tracer

?

My 576 works well except that a few of the #683 bulbs that illuminate the fiber optic scale factor readouts are burned out. The service manual is quite terse on the procedure to replace them, and completely ignores the situation where the burned out bulb is on the front readout circuit board.?

Does anyone have any practical experience and/or tips on how to replace the bulbs, on both the front and rear boards, with a minimum of risk to the fiber optic bundles?

Thanks,
Stan

Replacing readout lamps in Tek 576 curve tracer

#15788

My 576 works well except that a few of the #683 bulbs that illuminate the fiber optic scale factor readouts are burned out. The service manual is quite terse on the procedure to replace them, and completely ignores the situation where the burned out bulb is on the front readout circuit board.?

Does anyone have any practical experience and/or tips on how to replace the bulbs, on both the front and rear boards, with a minimum of risk to the fiber optic bundles?

Thanks,
Stan

Re: TDS 7404 configuration issue after replacing CMOS battery

#15787

On Fri, Jul 29, 2022 at 08:09 AM, Ozan wrote:

On Fri, Jul 29, 2022 at 07:01 AM, Stan wrote:

I made a backup of the original hard drive and then restored it from the Tek CDs. Unfortunately I still get the same behavior i.e., hanging on the DPO app startup splash screen. The service manual says to check connections to the acquisition board and the PPC board. I will open up the scope and look it over. Can any insight be gained by connecting a VGA monitor to the PPC board's video out connector? Will the seven-segment status LED help me out in this situation?

Thanks,
Stan
--
Hi Stan,
When the correct driver installed all video is routed to the LCD, VGA monitor should just show some text saying a similar thing. Seven-segment status LED is useful, TDS7000 series service manual starting page 6-69 shows what to expect. There is a simple troubleshooting tree on page 6-54 as a good starting point. Expected supply voltages are on page 6-56.

With the covers off another useful access point is the console port.

Ozan
?

Link to service manual: