Author Topic: Tektronix 465 Repair and Restoration (Read 137127 times)

w2aew · « **Reply #50 on:** October 25, 2013, 02:49:19 am »

Check all power supply voltages in the vertical amplifier and deflection amp circuits first. In the few times where I've come across a restricted or shifted vertical or horizontal range issue, it's mostly come down to a power supply issue.

Filter_head · « **Reply #51 on:** October 25, 2013, 09:33:24 am »

Quote from: w2aew on October 25, 2013, 02:49:19 am

Check all power supply voltages in the vertical amplifier and deflection amp circuits first. In the few times where I've come across a restricted or shifted vertical or horizontal range issue, it's mostly come down to a power supply issue.

Thank you, will report back with findings.

Whuffo · « **Reply #52 on:** October 25, 2013, 08:52:35 pm »

Thanks so much for the lovingly detailed description of your rehabilitation of this classic. I remember when they were new and how I lusted after one. Then during my field service days one of these traveled around the US with me. My how things have changed - but I'll always have fond memories of the 465.

Filter_head · « **Reply #53 on:** October 26, 2013, 01:40:24 pm »

Quote from: w2aew on October 25, 2013, 02:49:19 am

Check all power supply voltages in the vertical amplifier and deflection amp circuits first. In the few times where I've come across a restricted or shifted vertical or horizontal range issue, it's mostly come down to a power supply issue.

Taking the cover off and turning the unit on, a faint "sizzle" is heard in close proximity to the toggle switch adjacent to the PS transformer. The sizzle sound fades after 4-5sec. Switching the unit on and off can restore the sizzling noise. The PS caps are directly behind the switch.

Filter_head · « **Reply #54 on:** October 27, 2013, 07:44:57 pm »

Quote from: w2aew on October 25, 2013, 02:49:19 am

Check all power supply voltages in the vertical amplifier and deflection amp circuits first. In the few times where I've come across a restricted or shifted vertical or horizontal range issue, it's mostly come down to a power supply issue.

Low voltage PS magnitudes at the 5 TPs are all ok but the ripple is excessive in all of them (4-5X higher than spec). Ripple in 110V is close to 100mV (spec 20mV).
Replacing the caps will improve that.

Measured the voltages in the Vertical Amplifier, deflection plates (spec 34V, top and bottom), measured 34.1V and 32.7V, respectively.

SLJ · « **Reply #55 on:** October 27, 2013, 11:07:07 pm »

Excellent job on bringing this one back. My 465 is my favorite on the bench.

Whuffo · « **Reply #56 on:** October 29, 2013, 12:47:51 pm »

Quote from: Filter_head on October 27, 2013, 07:44:57 pm

Quote from: w2aew on October 25, 2013, 02:49:19 am
Check all power supply voltages in the vertical amplifier and deflection amp circuits first. In the few times where I've come across a restricted or shifted vertical or horizontal range issue, it's mostly come down to a power supply issue.

Low voltage PS magnitudes at the 5 TPs are all ok but the ripple is excessive in all of them (4-5X higher than spec). Ripple in 110V is close to 100mV (spec 20mV).
Replacing the caps will improve that.

Measured the voltages in the Vertical Amplifier, deflection plates (spec 34V, top and bottom), measured 34.1V and 32.7V, respectively.

Check / replace those filter caps - they're well past their "best by" date. Pay close attention to the dipped tantalum caps, they're known to be trouble in these scopes.

Filter_head · « **Reply #57 on:** November 11, 2013, 02:14:28 am »

I did find the problem in my particular 465.

A faulty film resistor in the first V to I stage of the amplifier board.

Couple of photos here. Replacement of the R4421 realized a fully functional amplifier board.

http://www.northreadingeng.com/Forums/index.php/topic,62.0.html

Wire Nut · « **Reply #58 on:** June 28, 2014, 08:06:13 pm »

Guys,
I know this is an old post... but I just got a 465 that is in good shape physically. It has manuals and probes; but no trace. I saw this post and it gives me a few things to look for, but first I need to get the cover off! Could someone be kind enough to tell me what to do? I only see two screws on the back and thought if I took those out maybe it would slide back and expose the guts- no such luck!
Thanks for any help you can provide.

Andy Watson · « **Reply #59 on:** June 28, 2014, 08:17:26 pm »

Quote from: Wire Nut on June 28, 2014, 08:06:13 pm

I only see two screws on the back and thought if I took those out maybe it would slide back and expose the guts-

Plus four screws in the feet/cable holders.

Chipguy · « **Reply #60 on:** July 26, 2014, 05:49:50 pm »

Nice restoraton !
I hope it will run without hassle for a long time

Martini · « **Reply #61 on:** June 09, 2015, 10:51:30 pm »

I got extremely lucky yesterday: someone gave me a 465

I took the cover off today to replace the power cord (it's from Switzerland and I live in France). I saw these two heatshrink tubes hiding something:

...what is it? Should I preserve it?

Also, I'd like to understand to what extend the regulating range does affect the scope.

EDF is giving us around 235V, am I right to assume the M position to be adequate?

alsetalokin4017 · « **Reply #62 on:** June 10, 2015, 12:17:03 am »

Aren't those just the splices where someone before you has replaced the power cord already?

Martini · « **Reply #63 on:** June 10, 2015, 03:49:13 pm »

Correct. I didn't think it was the mowt elegant solution so I replace the wires from the switch up.

Now it's alive (although a bit sick):

Ronbo · « **Reply #64 on:** June 10, 2015, 04:00:06 pm »

Looks very clean Martini, shouldn't take too much work.

Martini · « **Reply #65 on:** June 10, 2015, 08:28:28 pm »

Cosmetically, it looks very good.
It's clean and all the knobs are intact.

The calibrator shows the square wave:

Changing the timebase, it doesn't look so good:

And the triggering doesn't work as smoothly as it should (provided I understood its principle):

Obviously, channel 2 doesn't work:

I guess I'll create a new topic to seek your help guys.

tautech · « **Reply #66 on:** June 10, 2015, 08:33:14 pm »

Quote from: Martini on June 10, 2015, 08:28:28 pm

Cosmetically, it looks very good.
It's clean and all the knobs are intact.

I guess I'll create a new topic to ssek your help guys.

In the "Repair" board would be best.

hornm · « **Reply #67 on:** July 13, 2015, 03:39:02 pm »

Hi,

I'm aware that this thread is quite old but did that service manual ever get posted? I've tried to look for it but have not had too much luck. I recently bought a 465 scope and it also has no trace except when I press the beam finder. I've reset all components I could remove and found a ground plane wire that became loose and tacked that back on but still am not getting that trace. I would appreciate that service manual so I can have a more professional approach to solving this fix. I also need to get a few replacement parts.

Thanks

w2aew · « **Reply #68 on:** July 13, 2015, 04:10:51 pm »

Quote from: hornm on July 13, 2015, 03:39:02 pm

Hi,

I'm aware that this thread is quite old but did that service manual ever get posted? I've tried to look for it but have not had too much luck. I recently bought a 465 scope and it also has no trace except when I press the beam finder. I've reset all components I could remove and found a ground plane wire that became loose and tacked that back on but still am not getting that trace. I would appreciate that service manual so I can have a more professional approach to solving this fix. I also need to get a few replacement parts.

Thanks

It can be found here:
http://w140.com/mmm/tek-465-late.pdf
which is on this page (with a few more links):
http://w140.com/tekwiki/wiki/465

Note the the 465B is different, so be sure you have a non-B for the above links.

jh15 · « **Reply #69 on:** December 17, 2015, 07:23:29 am »

How are you coming along on this?

I have a 465 non-B also but it is ok although a bit old in the crt teeth.

I am retired from the grind, but was a test equipment department tech, boss, slave for avionics companies.

Found a way to heat my basement, so have 535, 575 curve tracer, 555, other storage Teks and HPs to play with during blizzards.
Don't plan to run any on UPS's.

Martini · « **Reply #70 on:** December 17, 2015, 04:13:40 pm »

I didn't touch it. I have a question, though...is the red grid supposed to be lit? If so, what's the most common issue with it.

Gerry Powell · « **Reply #71 on:** February 19, 2016, 04:39:01 am »

A friend and I are trying to repair his newly acquired 465 and have found a problem. The sweep variable red knob has taken a bump and it's depressed so far that you can just barely grab it to turn so I think the component it's connected to is damaged.
The main sweep works fine, but when the variable is turned the sweep disappears.
From what I can make of the manual, the variable sweep control is a pot ganged with a switch and it looks like the part number is 311-1701-00.
Any help appreciated.
thanks, Gerry

pez.diSpencer · « **Reply #72 on:** May 30, 2017, 04:47:27 am »

Wow, thanks for posting this and great work! The Tek465 has always been the image in my mind whenever someone mentions a scope, and I finally found one on ebay (😬) for a very good price, non-working. Definitely a gamble as it doesn't power-on, so I'm hoping major components aren't pulled (😰)...but the price was too good to pass up-- fair enough for the spare parts if it's deader'n dead, at least. I'll post the condition when it gets here, and I'll start another 465 restore thread if the job can be done!

P90 · « **Reply #73 on:** May 30, 2017, 05:07:58 am »

Tektronix orgy? lol

https://orangecounty.craigslist.org/ele/6148052200.html

pez.diSpencer · « **Reply #74 on:** May 30, 2017, 02:29:38 pm »

Quote from: P90 on May 30, 2017, 05:07:58 am

Tektronix orgy? lol

https://orangecounty.craigslist.org/ele/6148052200.html

I saw that on ebay too... Wish I was in California instead of Chicago (which is the case six months out of the year, regardless)!

The guy selling those also designed and sells a nifty and compact pyramid step generator for checking/calibrating your scope's horizontal timebase.

http://m.ebay.com/itm/CALIBRATION-AND-TESTING-DEVICE-FOR-TEKTRONIX-AND-ALL-QUALITY-OSCILLOSCOPES-/131782800534?hash=item1eaeddf496%3Ag%3AeAEAAOSwgApXCtGO&_trkparms=pageci%253A0c73d5e7-4544-11e7-8d50-74dbd180b80b%257Cparentrq%253A59c0bd7815c0a88bc6508856fffcad63%257Ciid%253A12


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Author Topic: Tektronix 465 Repair and Restoration (Read 137127 times)

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