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LVPS Caps for 465B

 

My 465B was exibiting intermittent loss of at least on LV rail which has now gone to full failure mode. More than one of the rails is well out of spec now and I suspect the problem is with the PS caps. One of them is checking around 110 ohms but while I'm in there, I plan to replace all five of them.

I have adapter discs made up to use snap-in caps and am wondering if anyone has done this before and what caps were used. I did a pass over Mouser's stock and have an initial list but if anyone has done this before and has a list, I'd be interested in seeing it.

Thanks,
Barry - N4BUQ
Manual FG504

 

Hello,Do you have an electronic manual for FG504 ?Series before 0400000
Thank you,Petre
2465 parts unit BIN $50

 

No affiliation. Has a good CRT and powers up.
<>
Re: Using a Tek sampling head

 

Mark, thank you for the hint. I've just found a photograph of an HP 1430A sampling head and the resemblance to the Soviet one is, shall we say, uncanny. I'm definitely going to do more research down this path!

Chris

On Mon, May 28, 2018 at 10:08 am, Mark Kahrs wrote:

Let me be heretical and suggest using an HP 1430 series head. They can be
made compatible w/ the S series but you'd have to roll-your-own interface.
They also have a very strange cable. But, it's another idea.



On Sun, May 20, 2018 at 3:53 PM, cmjones01 <chris@...> wrote:

I have much enjoyed the recent discussion here about the 7T11/7S11/7S12
sampling plugins and have learned a lot from the contributions.

I have a long-term quest to get my Soviet Ya4S-100/Ya4S-101 sampling
plugins working properly. They're roughly equivalent to the 7T11 and 7S11
but with some neat features, most notably a delta delayed timebase and
slideback-type voltage measurement, both with digital display on the
scope's readout. The problem is that I don't have the sampling head for
them. I'm searching high and low for one (and learning quite a lot of
Russian in the process) but they're like hen's teeth and always seem to
have gone missing. The official sampling head is a dual channel feed
through sampler with SR50-262 (almost identical to 'N' type) connectors for
input and output. The good news is that the schematic is available, though
seems to have been drawn by someone whose aim was to minimise the use of
paper and ink rather than to create useful documentation.
Re: Help needed with no trace no beamfinder on 465 (not b)

 

Oxidation of TO-3 transistor socket contacts have been noted in the past. If Q1418 is socket-ed, remove, clean the leads, and re-install.
Re: Tek 7904 CRT

 

Are you asking is the plugins from 7613 work with 7904 , asnwer is yes as long as its a 7000 series it should work.
On Mon, May 28, 2018 at 11:56 AM, Jeff Urban<JURB6006@...> wrote: Will one from a 7613 work ?
Re: Using a Tek sampling head

 

Let me be heretical and suggest using an HP 1430 series head. They can be
made compatible w/ the S series but you'd have to roll-your-own interface.
They also have a very strange cable. But, it's another idea.

On Sun, May 20, 2018 at 3:53 PM, cmjones01 <chris@...> wrote:

I have much enjoyed the recent discussion here about the 7T11/7S11/7S12
sampling plugins and have learned a lot from the contributions.

I have a long-term quest to get my Soviet Ya4S-100/Ya4S-101 sampling
plugins working properly. They're roughly equivalent to the 7T11 and 7S11
but with some neat features, most notably a delta delayed timebase and
slideback-type voltage measurement, both with digital display on the
scope's readout. The problem is that I don't have the sampling head for
them. I'm searching high and low for one (and learning quite a lot of
Russian in the process) but they're like hen's teeth and always seem to
have gone missing. The official sampling head is a dual channel feed
through sampler with SR50-262 (almost identical to 'N' type) connectors for
input and output. The good news is that the schematic is available, though
seems to have been drawn by someone whose aim was to minimise the use of
paper and ink rather than to create useful documentation.

The sampling plugin has a 19-way connector for the sampling head. This
carries +/-15V, the signal and feedback for each channel, a single strobe,
and a mysterious signal called 'threshold' which looks like a TTL logic
output which alternates state on each trigger.

The good news is that my sampling plugins seem to be working well and all
the signals on the connector do the right things, so the project is worth
pursuing. My idea is to create an adapter cable so I can use Tek S-series
sampling heads until I find the original one. I don't have any S-series
heads at the moment, only SD-22 and SD-24 ones which involve too much
software, so I'd have to buy one to try out.

I've looked at the manuals for the 7S11 and various sampling heads. Is
there a clear specification anywhere of the interface, for example the
amplitude of the strobe pulse and the signal and feedback connections? I
would be quietly amused if the Soviet system turned out to be electrically
compatible with the Tek one...

All advice and thoughts much appreciated,
Chris
Re: My 422

 

Hi Jeff-
family issues and life stuff managed to derail ALL of my projects ( the 422 pwr sply, the 475 ps with issues, other radio projects ), however I did manage to get the supply working without a load (, hey this thing works down to 6V input!!! output Voltages are high but as expected!.) I know not recommended, under the load of the scope I noticed that it has issues too! so I have to find the faults in the scope before moving fwd.

the waveforms in the pwr sply look close to the ones in the book. I did notice that with something drawing too much current on the output it is exhibiting a similar issue as yours. Q1184 gets noticeably warmer than Q1174 as the input V increases. ( I also rises....yep, go figure, normal). I want to know why!
I will post my method and results at a later time. John's repair ( with the MJE1660) made me go back to my original premise that those transistors really do not matter and good old 2N3055/2n5881/2n5882 work just fine. just mounting issues with the TO-3 case. (currently they are mounted to an external heat sink)

I will go into monitor mode for a while longer.
Tnx for the assistance. It has been appreciated.
¸é±ð²Ô¨¦±ð

On 2018-05-28 09:01 AM, Jeff Urban wrote:
It is going on the back burner. I am going to put it together for its own safety. I am out of ideas and last I looked so was everyone, so I might just use it as a 12 volts scope or something...

If anyone gets any ideas I am all ears. For now I got bigger fish to fry, which ummm, by the way...

Yup, those 7000 series are next. Coming soon.
Re: Help needed with no trace no beamfinder on 465 (not b)

 
Edited

OK, thanks for correcting me.

I unsoldered that ground link you circled, plugged P1445 back in, PDA lead still unplugged.

I still get nothing on screen, and the reading at TP1423 is still low... It seems as I hold the positive lead of my meter on to TP1423 that the reading fluctuates.. starting around -100V then gradually climbing... up to about -160V last I checked, as though some capacitor is charging? After about 30 minutes it seemed to have stabilized at about -102V. I also notice that one of the neon lights nearby flashes on briefly when I first touch the TP1423 with the meter lead.
My 422

 

It is going on the back burner. I am going to put it together for its own safety. I am out of ideas and last I looked so was everyone, so I might just use it as a 12 volts scope or something...

If anyone gets any ideas I am all ears. For now I got bigger fish to fry, which ummm, by the way...

Yup, those 7000 series are next. Coming soon.
Re: Tek 7904 CRT

 

Will one from a 7613 work ?
Re: Help needed with no trace no beamfinder on 465 (not b)

 

No, no, no. You do not unplug P1445. That stays put.
Did you look at the picture I posted yesterday? I circled the part you need to UNSOLDER to open the ground to the HV Multi.

----- Original Message -----
From: "Keith Ostertag" <stuff@...>
To: <[email protected]>
Sent: Monday, May 28, 2018 11:25 AM
Subject: Re: [TekScopes] Help needed with no trace no beamfinder on 465 (not b)


Thanks you for that clarification!

OK, so I unplugged P1445 and the PDA lead, then powered up and gave it some time to warm up.

Nothing on the screen even when beamfinder pressed, and TP1423 HV test point still reads about -87 volts.

So... that means the HV mulitplier is not dead? Or at least it means something else is causing the problem?
Re: Help needed with no trace no beamfinder on 465 (not b)

 

Thanks you for that clarification!

OK, so I unplugged P1445 and the PDA lead, then powered up and gave it some time to warm up.

Nothing on the screen even when beamfinder pressed, and TP1423 HV test point still reads about -87 volts.

So... that means the HV mulitplier is not dead? Or at least it means something else is causing the problem?
Re: Help needed with no trace no beamfinder on 465 (not b)

 

Yes, that is the connector for the HV lead that goes to the CRT Post Deflection Accelerator (PDA) electrode. The PDA is a conducting coating on the inside of the tube funnel that starts after the horizontal deflection plates.. You should be aware that the outer coating of the tube forms a capacitor that holds a high voltage charge for a long time. If you disconnect the HV connector, be careful that the lead does not come in contact with any circuitry as it will damage it.

----- Original Message -----
From: "Keith Ostertag" <stuff@...>
To: <[email protected]>
Sent: Monday, May 28, 2018 9:09 AM
Subject: Re: [TekScopes] Help needed with no trace no beamfinder on 465 (not b)


Is this the PDA? /g/TekScopes/photo/49286/2?p=Name,,,20,1,0,0

I was thinking it was the end of the HV mulitplier...
Re: Help needed with no trace no beamfinder on 465 (not b)

 

Yes, that is the connector for the HV lead that goes to the CRT Post Deflection Accelerator (PDA) electrode. The PDA is a conducting coating on the inside of the tube funnel that starts after the horizontal deflection plates.. You should be aware that the outer coating of the tube forms a capacitor that holds a high voltage charge for a long time. If you disconnect the HV connector, be careful that the lead does not come in contact with any circuitry as it will damage it.

----- Original Message -----
From: "Keith Ostertag" <stuff@...>
To: <[email protected]>
Sent: Monday, May 28, 2018 9:09 AM
Subject: Re: [TekScopes] Help needed with no trace no beamfinder on 465 (not b)


Is this the PDA? /g/TekScopes/photo/49286/2?p=Name,,,20,1,0,0

I was thinking it was the end of the HV mulitplier...
Re: Help needed with no trace no beamfinder on 465 (not b)

 

Is this the PDA? /g/TekScopes/photo/49286/2?p=Name,,,20,1,0,0

I was thinking it was the end of the HV mulitplier...
Re: PG502 Failure points?

 

Now it's coming back to me. The 10H was a geometry shrink with reduced
internal capacitances and higher fT so they could improve speed and lower
power. Pinout issues aside, the MC10H109 might well work in place of the
MC1660, the only way to know would be to try it. That would be my second
choice, sourcing an MC1660 would be my first.

Steve
Re: Help needed with no trace no beamfinder on 465 (not b)

Chuck Harris
 

Post Deflection Accelerator. It is the Anode cap at
the edge of the CRT's funnel usually to the left of
the screen.

-Chuck Harris

Keith Ostertag wrote:

Thanks! That's jumper P1445, I believe.

What's the "PDA lead "? I don't recognize what PDA stands for...
Re: Deceptive fault in a 535A

 

Had same fault many years ago,replaced the resonator cap with, from memory, a 0.001/1000V
Styroseal (white) cap...should outlast the scope.
John
Re: Help needed with no trace no beamfinder on 465 (not b)

 

Yes the 1330 manual is the correct manual for your unit. while the 1861 manual can be useful at times, as it pertains to your unit? you need to be very careful . Some circuits in the later manual are very different and some are essentially unchanged from the earlier version.

good luck
-dc
manuals@...

On 5/27/2018 9:24 PM, Keith Ostertag wrote:
My 465 SN is B175976.

I am looking at a manual marked "tek-070-1330-00" (236 pages, with yellow addendum pages added in the back), as well as a manual for later version 465's (070-1861-00, B250000 & up, says Rev B, June 1975, 291 pages).

I think the first is the correct one, but it is more limiting (for instance, no trouble shooting flowchart).


--
Dave
Manuals@...
www.ArtekManuals.com
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