Author Topic: Tek 465, no vertical movement or display, only a horizontal line. (Read 2094 times)

tekguy465 · « **on:** October 29, 2019, 10:29:39 pm »

How do I fix a Tek 465 that displays a horizontal line, but nothing above or below, nor can I move the line up or down.

Everything else on the scope seems fine.

Thank you in advance!

maginnovision · « **Reply #1 on:** October 29, 2019, 10:42:51 pm »

Check voltages, then check preamp.

tekguy465 · « **Reply #2 on:** October 29, 2019, 10:47:36 pm »

Newby question, but where would I find the information to check the voltages and preamp?

tggzzz · « **Reply #3 on:** October 29, 2019, 10:50:30 pm »

Verify PSU rail voltages and ripple.

Check wires between CRT vertical plates and amplifier haven't fallen off.

Check some vertical amplifiers by observing ch1 vertical output on back panel.

Follow faultfinding procedures in the service manual; trivial to find on the web.

tekguy465 · « **Reply #4 on:** October 29, 2019, 11:04:07 pm »

Again, newby questions:

1. How do I go about verifying PSU rail voltages and ripple?

2. Where are the CRT vertical plates? Where is the amplifier?

3. How do I check some vertical amplifiers by observing ch 1 vert out? Would I need another scope for this?

My bad for the questions, I am very very new to this. I wouldn't have asked on here if I hadn't the last 2 days on the internet trying to find an answer to my problem I have 5 - tek 465's and only one of them works properly. The other 4 all have problems. 2 don't display at all, and the other 2 only do the horizontal line thing.

If I could find somebody in Orange County to fix them, I would just use them instead of trying to it myself.

0culus · « **Reply #5 on:** October 29, 2019, 11:08:26 pm »

First things first, get the service manual. Artek should have high quality scans available for a modest fee.

http://artekmanuals.com/manuals/tektronix-manuals/

tggzzz · « **Reply #6 on:** October 29, 2019, 11:16:54 pm »

Quote from: tekguy465 on October 29, 2019, 11:04:07 pm

Again, newby questions:

1. How do I go about verifying PSU rail voltages and ripple?

2. Where are the CRT vertical plates? Where is the amplifier?

3. How do I check some vertical amplifiers by observing ch 1 vert out? Would I need another scope for this?

My bad for the questions, I am very very new to this. I wouldn't have asked on here if I hadn't the last 2 days on the internet trying to find an answer to my problem I have 5 - tek 465's and only one of them works properly. The other 4 all have problems. 2 don't display at all, and the other 2 only do the horizontal line thing.

If I could find somebody in Orange County to fix them, I would just use them instead of trying to it myself.

https://lmgtfy.com/?q=tektronix+465+service+manual&s=g for free downloadable service manuals

james_s · « **Reply #7 on:** October 29, 2019, 11:19:06 pm »

Can you find someone to help you? I don't mean this to sound rude, but if you have to ask such basic questions what are you going to do with a Tek 465 if you get it working? I'm not really sure you should be poking around inside it until you have a bit more experience, it is both delicate and potentially dangerous. Nice instrument when it works though. The 465 is a legendary classic.

tggzzz · « **Reply #8 on:** October 29, 2019, 11:38:50 pm »

Yeah, that's valid.

I wonder if the OP realises there is -2450V exposed inside the case, and 15.5kV on one wire.

maginnovision · « **Reply #9 on:** October 30, 2019, 12:16:12 am »

Quote from: tekguy465 on October 29, 2019, 11:04:07 pm

Again, newby questions:

1. How do I go about verifying PSU rail voltages and ripple?

2. Where are the CRT vertical plates? Where is the amplifier?

3. How do I check some vertical amplifiers by observing ch 1 vert out? Would I need another scope for this?

My bad for the questions, I am very very new to this. I wouldn't have asked on here if I hadn't the last 2 days on the internet trying to find an answer to my problem I have 5 - tek 465's and only one of them works properly. The other 4 all have problems. 2 don't display at all, and the other 2 only do the horizontal line thing.

If I could find somebody in Orange County to fix them, I would just use them instead of trying to it myself.

Why do you have 5 if you can't fix one? Is that orange county New York, California, another state? I'm not trying to be mean but I don't think old crt scopes are a good place to start learning to repair things.

tekguy465 · « **Reply #10 on:** October 30, 2019, 12:29:23 am »

I literally have nooooo experience working on any electronics.

The reason I have 5 is because I got a good deal on them and I am using them in a live setting for display for sound waves.

Does anybody know of a place/person to go in Orange County/LA California?

maginnovision · « **Reply #11 on:** October 30, 2019, 12:36:08 am »

I'm in LA but have no time. With no experience you have virtually no chance. Maybe someone knows someone around SoCal that can help you but a repair of 1 will probably cost more than the purchase of a couple or all of them

0culus · « **Reply #12 on:** October 30, 2019, 12:37:50 am »

I don't know of any specifically, but I'd say you should absolutely find someone else to help you since you are a complete novice. Messing around crt and tube circuits is not like dinking around with 5V microcontroller stuff. There's ways to straight up kill yourself if you put your hand or a tool in the wrong spot. NOT worth it.

Another way to find someone would be to post in the TekScopes mailing list. I know there are some cali peeps on there. Perhaps one could help you out locally.

tekguy465 · « **Reply #13 on:** October 30, 2019, 12:38:56 am »

How much are we talking here?

I just made another post on the repair section asking people if they knew of anybody.

TK · « **Reply #14 on:** October 30, 2019, 12:43:20 am »

If you have no electronics experience, how do you know they are broken? Have you connected any probe to the input?

tggzzz · « **Reply #15 on:** October 30, 2019, 12:44:11 am »

Quote from: tekguy465 on October 30, 2019, 12:29:23 am

I literally have nooooo experience working on any electronics.

The reason I have 5 is because I got a good deal on them and I am using them in a live setting for display for sound waves.

In that case you will only damage the scopes or yourself. The internal voltages are lethal, and some components can be easily damaged.

You should sell them on fleabay, and buy some cheap working 5/10/20MHz scopes. The traditional price is $1/MHz.

bob91343 · « **Reply #16 on:** October 30, 2019, 12:48:43 am »

Apparently the vertical deflection amplifier isn't putting out a signal. That's either because

1. it has lost power
2. it has no signal input
3. the CRT is bad

Find the vertical deflection plates and see if the voltage there is what it should be.

If you like, you can bring it here and we can fix it. I have a working 465 also. I live in the San Fernando valley.

Bob K6DDX

tautech · « **Reply #17 on:** October 30, 2019, 01:05:20 am »

Quote from: tekguy465 on October 30, 2019, 12:38:56 am

How much are we talking here?

I just made another post on the repair section asking people if they knew of anybody.

Really what matters is your experience with high voltages, your safety practices, tools you have and your ability to study and understand the procedures called for in the service manual.
Once you have all these things under control repairing scopes is addictive and fun as most often the faults are simple ones.

If you have a handle on the bench work then understanding the service manuals and CRO operation are the next challenges and this is no 5 minute wonder for the novice.
You'll need this:
http://www.sphere.bc.ca/test/tek-parts/troubleshooting-scopes.pdf

Plus a basic understanding of how CRO's work and the need for the various voltage rails inside them.
465's have a habit of shorted tants as early designers weren't aware of the max voltage margin they needed in order to be reliable.

One of the golden rules already offered is thou shalt check voltages ! But that's not the end, you need to be sure rails also meet ripple specs.
The LV rails are bread and butter much like the HV for the CRT plate drives but the EHT is where max caution need be engaged as it's normally some 2kV !
PDA is another scary level higher but luckily you generally don't need to bother with it as it's derived from the EHT and if its working to spec then PDA normally is too.

If you can get your head around all that and can manage the necessary safety precautions with high voltages you too can repair these 465's and there's plenty of experienced help here to guide you.
But first, read, study and read some more !

Quote from: tekguy465 on October 30, 2019, 12:29:23 am

I literally have nooooo experience working on any electronics.

Bugger !

Best advice then is to move them on and get some experience with safer projects.

andy3055 · « **Reply #18 on:** October 30, 2019, 01:41:22 am »

On no account should you open the case!

james_s · « **Reply #19 on:** October 30, 2019, 03:52:32 pm »

I would sell the 465's to someone that actually knows how to use one and pick up some cheap low bandwidth off-brand analog scopes. A 465 is a nice instrument in working order and I'm betting someone who knows what they're doing could get them going without too much trouble. These are definitely a project for an experienced tech, a complete beginner will destroy them at best, killing themselves in the process at worst.

bob91343 · « **Reply #20 on:** October 31, 2019, 04:49:42 pm »

I can help. Just let me know. I live in the San Fernando Valley, as I mentioned above, and have a working 465. I'd be willing to get yours working or make a deal for your broken gear.

Let me know by PM and we can work out something.

Bob


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Author Topic: Tek 465, no vertical movement or display, only a horizontal line. (Read 2094 times)

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