Thanks, Tom. The existing diodes are tiny glass(?) cylinders with metal ends that clip into small holders (much like the old fashioned clip-in fuses). I suppose I'll be doing some plumbing for whatever I find to replace them.
Thanks,
Barry - N4BUQ
toggle quoted message
Show quoted text
----- Original Message -----
From: "Tom Lee" <tomlee@...>
To: "tekscopes" <[email protected]>
Sent: Friday, December 17, 2021 7:14:57 PM
Subject: Re: [TekScopes] Type 106
Based on the fast-rise circuitry of the 106 and PG506 being similar and
having similar specs, you would seem to have several good Si-Schottky
candidates. A few that come to mind are:
MBD101
BAV17
HSMS-282x (15V breakdown makes these an upgrade over the stock diodes)
These have slightly higher capacitance than the GaAs originals, but it's
not enough to matter.
I'm sure others will chime in shortly with their recommendations.
-- Cheers
Tom
--
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
350 Jane Stanford Way
Stanford University
Stanford, CA 94305-4070
On 12/17/2021 16:11, n4buq wrote:
Speaking of a 106, anyone know anything about the GaAs diodes in the Fast Rise
outputs? I think one or two of mine are bad. The +OUTPUT works but not the
-OUTPUT. Input to the two diodes on the -OUTPUT side looks okay but at the
junction between the two, the signal is not correct and the output is not
correct at all.
I've never seen diodes constructed like these before and don't expect I'll find
direct replacements but am wondering could be used as replacements.
Thanks,
Barry - N4BUQ
----- Original Message -----
From: "saipan59 (Pete)" <saipan1959@...>
To: "tekscopes" <[email protected]>
Sent: Friday, December 17, 2021 4:24:27 PM
Subject: Re: [TekScopes] Type 106
Ah, so your earlier "my bad" message meant to say that nothing is actually wrong
with the +/-10 rails. Got it.
However, regarding:
"Instead of checking voltages between chassis ground and directly at both
emitters, I probed between ground and + C215/ C218. According to the
schematic, this should be the same. But apparently not"
You MUST get the same values at the Emitters and at +C215 and -C218 ! If you
don't, you've got a measurement problem, OR those caps are not actually
connected like they should be.
Note that those rails *may* appear to work fine, even if C215 and C218 are
missing...
Pete
