Re: Re-capping an HP-130 Scopes
The outside foil of condensers is usually connected to ground for shielding. If this is ignored in the IF section of some receivers, oscillations and instability can be a problem. In a scope or audio
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greenboxmaven
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#119753
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Re: Re-capping an HP-130 Scopes
Mr Carlson's Lab
https://www.youtube.com/c/MrCarlsonsLab/videos
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Glen Slick
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#119752
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Re: HP200CD oscillator
Interesting that the letter was dated June 13th, as that is James Clerk Maxwell's and Thomas Young's (Young's modulus and the wave theory of light) birthday. And my younger son's.
Thomas Young was
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Jim Ford
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#119751
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Re: Re-capping an HP-130 Scopes
Hmmm... could you please direct me to Mr C? I couldn't find him online; my google-fu must be rusty.
And, what does the foil side of a capacitor sound like? Versus the other side? I'd have to try
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Jim Ford
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#119750
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Re: HP200CD oscillator
The older tubes are OA3, OB3, OC3, and OD3. These are also (IIRC) VR75, VR90, VR104, and VR150.? Don't quote me on the VRxxx tubes, because I haven't dealt with them in a good 25 years (or more).? I
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Harvey White
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#119749
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Re: HP200CD oscillator
Most power amp output tubes (6AQ5, 6L6, EL34, etc) will glow a beautiful blue.
Suspect the EL86 would as well.
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Mark Bielman
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#119748
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Re: HP200CD oscillator
Another tube that glows orange is VR75.
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Bob Albert <bob91343@...>
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#119747
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Re: HP200CD oscillator
There's pretty much three types of tubes in terms of what's inside the envelope.? Don't mean triode, etc.
Voltage regulators, i.e 5651 or OD3, are essentially BIG neon lamps that glow, and the
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Harvey White
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#119746
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Re: HP200CD oscillator...
After looking at the pictures I can say for sure that this tube is no good. I would suggest replacing both of them. They are not worth testing in a tube tester unless you're just curious how a
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Burt K6OQK
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#119745
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Re: HP200CD oscillator
These were the tubes in the unit when it arrived. Both of these were marked EL86 I recall before cleaning the dust off them and removing the marking inadvertently. They are both in shields so I
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Richard Merifield
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#119744
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Re: HP200CD oscillator
Do you ship to Australia Tom?
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Richard Merifield
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#119743
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Re: Agilent/Keysigh ESG series CLIP
Hi Xu
That makes you the king pin as you have dun a marvellous job with extending the life of HP equipment
regarding old corespondents I think we may be missing those but if i find any think i will
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Paul Bicknell
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#119742
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Re: HP200CD oscillator
?? I am curious about those glowing tubes. The one that glows pink and purple might be very gassy but the only tubes I've seen that glow orange are 5651 voltage reference tubes. I wonder if you mght
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Richard Knoppow
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#119741
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Re: HP200CD oscillator
You should replace both tubes as the gassy one at least? looks like it has had a hard life. That might be all you need to get the 200CD going again. BTW the voltages quoted on the schematic are all
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Morris Odell
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#119740
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Re: Re-capping an HP-130 Scopes
Yep been a Mr C fan for a while.? He designed a neat little rig that checks for foil side of a cap.? I think my second build ever.? Works great.? I even took apart a few spare modern caps to see
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John Scoles
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#119739
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Re: Agilent/Keysigh ESG series CLIP
Chief cook and bottle washer! ;)? ? Jim Ford?Sent from my Verizon, Samsung Galaxy smartphone
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Jim Ford
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#119738
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Re: Agilent/Keysigh ESG series CLIP
Em 27/10/2021 16:18, Xu Wang via groups.io escreveu:
^^^^^^^^^
HAHAHA I LOLed =)
Congratulations for your nice products, Xu!
73 de PU2SEX Alexandre
--
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Alexandre Souza
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#119737
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Re: Agilent/Keysigh ESG series CLIP
Hi Paul,
I was talking about license to reproduce and distribute HP manuals. If there is some correspondence from HP that grants the permission to the public to do so, like in the case with Tek, it
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Xu Wang
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#119736
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Re: Looking to buy HP6268B 40V 30A Power Supply
Alex:
I bought and rebuilt a 6268B,I was told it was working,which it was not.
All of the black diodes were rendered to grey dust but easily replaced. How this happened, I don't have a clue.The only
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Wallace Gasiewicz
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#119735
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Re: HP200CD oscillator
I would agree - your MK1 Eyeball Tube Tester has told you all you need to know!
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Adrian Nicol
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#119734
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