Help with Tek 214 Please!


newcastle2000@...
 

Hi All

I hope that this is the right way to Post!

I have a Tek 214. It all seems to be working except that I can't get the storage function to be anything like right!

The only way I can see a trace in storage mode is with the brilliance fully up and the scope defocussed. In that mode the whole screen is flooded. With the scope set normally and selecting 'Store' all I get is a light green blob on roghly the middle of the screen, no trace?

I have the manual and have tried to set it up but without a stored trace the manual is no help.

All the tube voltages seem correct.

The worst part is that I have no idea how it should be working, I've looked for a video of the scope in use but can't find one.

Can anyone give any pointers please? A video would be great. A list of voltages would be wonderful, there are some in the manual but they seem OK. Something must be amiss.

Here is a YouTube video of the problem - Note the trace is very slow and the video recorder has made it look 'dashed' - it's quite normal in fact.

https://youtu.be/Hl-mq09-G2c

I'm bouncing the STORE button in the last bit and you can see something like I'd expect the store fuction to do.

Any help gratefully recieved!

James


Miguel Work
 

I had the similar problem, I remember that the problem was the switches, or the switches board connector in pcb.

https://www.youtube.com/watch?v=R0ozSOYHqqc



-----Mensaje original-----
De: TekScopes@groups.io [mailto:TekScopes@groups.io] En nombre de newcastle2000@hotmail.com
Enviado el: domingo, 30 de mayo de 2021 19:06
Para: TekScopes@groups.io
Asunto: [TekScopes] Help with Tek 214 Please!

Hi All

I hope that this is the right way to Post!

I have a Tek 214. It all seems to be working except that I can't get the storage function to be anything like right!

The only way I can see a trace in storage mode is with the brilliance fully up and the scope defocussed. In that mode the whole screen is flooded. With the scope set normally and selecting 'Store' all I get is a light green blob on roghly the middle of the screen, no trace?

I have the manual and have tried to set it up but without a stored trace the manual is no help.

All the tube voltages seem correct.

The worst part is that I have no idea how it should be working, I've looked for a video of the scope in use but can't find one.

Can anyone give any pointers please? A video would be great. A list of voltages would be wonderful, there are some in the manual but they seem OK. Something must be amiss.

Here is a YouTube video of the problem - Note the trace is very slow and the video recorder has made it look 'dashed' - it's quite normal in fact.

https://youtu.be/Hl-mq09-G2c

I'm bouncing the STORE button in the last bit and you can see something like I'd expect the store fuction to do.

Any help gratefully recieved!

James


newcastle2000@...
 

HI Miguel

The video is great - the scope really snaps the stored traces in the way you would imagine for a bistable display!

I don't think that any of my switches are giving problems though! Do you do anything specific when changing from normal to Store mode?


Cheers
James


Miguel Work
 

Hi James,

Yes, I press store, and then erase to erase screen:

https://www.youtube.com/watch?v=3zLCN68xtTI

Cheers

-----Mensaje original-----
De: TekScopes@groups.io [mailto:TekScopes@groups.io] En nombre de newcastle2000@hotmail.com
Enviado el: martes, 1 de junio de 2021 11:44
Para: TekScopes@groups.io
Asunto: Re: [TekScopes] Help with Tek 214 Please!

HI Miguel

The video is great - the scope really snaps the stored traces in the way you would imagine for a bistable display!

I don't think that any of my switches are giving problems though! Do you do anything specific when changing from normal to Store mode?


Cheers
James


newcastle2000@...
 

Hi Miguel

You have provided a missing part of the issue. I assumed that pressing STORE set the scope up to store - but from your video it seems that you then need to press ERASE which I now assume charges the screen and makes it ready to store a sweep. Fiddling about I have got to the following point where I at least get a trace and a store - even if it is out of focus! I can't find anywhere in the manual that tells you how to operate the scope in store mode!

https://www.youtube.com/watch?v=HxzWbg9lGx8

I will start again from here! Your help is much appreciated!


James


Dave Voorhis
 

Turn the intensity down, and the out-of-focus should resolve.

-----Original Message-----
From: TekScopes@groups.io <TekScopes@groups.io> On Behalf Of newcastle2000@hotmail.com
Sent: 03 June 2021 09:59
To: TekScopes@groups.io
Subject: Re: [TekScopes] Help with Tek 214 Please!

Hi Miguel

You have provided a missing part of the issue. I assumed that pressing STORE set the scope up to store - but from your video it seems that you then need to press ERASE which I now assume charges the screen and makes it ready to store a sweep. Fiddling about I have got to the following point where I at least get a trace and a store - even if it is out of focus! I can't find anywhere in the manual that tells you how to operate the scope in store mode!

https://www.youtube.com/watch?v=HxzWbg9lGx8

I will start again from here! Your help is much appreciated!


James


Miguel Work
 

Yes!

Much better. Firs put scope in normal sweep, focused trace, I think that now is x10, and then try with store.

Your 214 is a new toy for you? Or it broke down? did you have problems with leakaging batteries?

Thanks

Regards

Miguel



-----Mensaje original-----
De: TekScopes@groups.io [mailto:TekScopes@groups.io] En nombre de newcastle2000@hotmail.com
Enviado el: jueves, 3 de junio de 2021 10:59
Para: TekScopes@groups.io
Asunto: Re: [TekScopes] Help with Tek 214 Please!

Hi Miguel

You have provided a missing part of the issue. I assumed that pressing STORE set the scope up to store - but from your video it seems that you then need to press ERASE which I now assume charges the screen and makes it ready to store a sweep. Fiddling about I have got to the following point where I at least get a trace and a store - even if it is out of focus! I can't find anywhere in the manual that tells you how to operate the scope in store mode!

https://www.youtube.com/watch?v=HxzWbg9lGx8

I will start again from here! Your help is much appreciated!


James


Jim Adney
 

For a scope with screen storage, as yours appears to be, the usual procedure is as follows:

Get the scope working under non-storage first: vert. size, focus, time base, intensity, etc.

Switch time base to single sweep.

Press Store and wait for screen to flood and then slowly clear. If it never clears, that's something that may need internal adjustment.

Press the Single-Sweep trigger (or Reset) button to trigger a single sweep. If you don't see anything, you may have to turn up the Intensity to get enough writing on the screen to register.

When you're finished viewing the stored image, press Erase and then re-trigger the sweep for a new stored image.

When you're done with storage, press the Store button again to release it. You'll probably have to turn the Intensity down.


 

On Thu, Jun 3, 2021 at 11:47 AM, Miguel Work wrote:


I assumed that pressing STORE set the scope up to store - but from your video
it seems that you then need to press ERASE
Notwithstanding what Jim Adney wrote a few moments ago, this is the way the 214 works. The screen does not flood and then clears by itself.

Raymond


newcastle2000@...
 

Hi All, thanks for the replies.

I've had this scope for 10 years in a cupboard - now I've retired (Hurrah) I'm repairing everything that wasn't. So far I've fixed two other Tek scopes - LOVE the 7D20.

Obviously the batteries were the first thing to be changed - I just put equivalents in, charged them up and they work great, fit well too.

The scope works just fine in the normal mode (though the triggering may prove to be a problems - but that's for later). The brillaince does need to be almost fully clockwise though.

In STORE mode there is no trace unless I adjust the brilliance and the grid voltage. This gives the defocussed trace you see, but at least there is a trace. Previously I had to look at the X-Plate voltages to convince myself that there was a sweep but it wasn't visible. What was also getting to me was the operation of the scope - I couldn't find a video of it working in STORE mode until Miguel provided one and the method of operation too.

I need to go back and check all the tube voltages I think. The manual has waveforms and voltages but it's not clear when they apply - clearly some relate to operation in STORE mode (the ones in the rounded rectanges?) and some normal? The set-up procedure is quite involved, I've not go to a point where I can follow it as I didn't have a trace. I'm hoping that the odd maths you need to do will help sort my problem!

Cheers
James


Miguel Work
 

I remember that I had broken and rotten wires in CRT socket too

https://groups.io/g/TekScopes/album?id=66992




-----Mensaje original-----
De: TekScopes@groups.io [mailto:TekScopes@groups.io] En nombre de newcastle2000@hotmail.com
Enviado el: jueves, 3 de junio de 2021 22:10
Para: TekScopes@groups.io
Asunto: Re: [TekScopes] Help with Tek 214 Please!

Hi All, thanks for the replies.

I've had this scope for 10 years in a cupboard - now I've retired (Hurrah) I'm repairing everything that wasn't. So far I've fixed two other Tek scopes - LOVE the 7D20.

Obviously the batteries were the first thing to be changed - I just put equivalents in, charged them up and they work great, fit well too.

The scope works just fine in the normal mode (though the triggering may prove to be a problems - but that's for later). The brillaince does need to be almost fully clockwise though.

In STORE mode there is no trace unless I adjust the brilliance and the grid voltage. This gives the defocussed trace you see, but at least there is a trace. Previously I had to look at the X-Plate voltages to convince myself that there was a sweep but it wasn't visible. What was also getting to me was the operation of the scope - I couldn't find a video of it working in STORE mode until Miguel provided one and the method of operation too.

I need to go back and check all the tube voltages I think. The manual has waveforms and voltages but it's not clear when they apply - clearly some relate to operation in STORE mode (the ones in the rounded rectanges?) and some normal? The set-up procedure is quite involved, I've not go to a point where I can follow it as I didn't have a trace. I'm hoping that the odd maths you need to do will help sort my problem!

Cheers
James