Short of testing in an amp a static test would be the only other
reasonably reliable way. At least it tells you it conducts!
A test jig still needs to be built so you need a socket, blower, sheet
metal, meters, and a source of filament, bias and HV. Follow the tube
curves in the spec sheet.
So now back to finding someone you can trust to really test them in an
amp!
Carl
KM1H
----- Original Message -----
From: "Kevin LaHaie" <klahaie@centricata.com>
To: <Amps@contesting.com>
Sent: Thursday, July 31, 2008 12:06 AM
Subject: [Amps] 8877 Advice
> Lucky Me! (Maybe?)
>
> Received a pair of Eimac 8877's from a friend, condition unknown but
> initial checks show no shorts, and physically one appears to have very
> little use (lettering still bright, just some evidence of light dust
> in
> the cooling fins) and the other could pass for NOS. Of course,
> appearances mean nuthin'
>
> They are both date code 8750, and I assume this means 1987, which
> rumor
> has it was a bad year for these. There is an engraving in the top of
> the anode compartment, CYR-058 and CYR-068, so these appear to be
> practically identical, certainly from the same run.
>
> I don't have anything that runs the 8877, but I would love to build
> something to use them. But, before I start procuring the necessary
> sockets and chimneys etc. to incorporate these into a project, I
> wonder
> if there is a somewhat definitive test to see if these are good or
> just
> pretty paperweights!
>
> I suppose I will get lots of offers to send these to you for an
> in-amplifier test, only to find out that they aren't worth the return
> freight hihi.
>
> I do have access to a professional HiPot tester, and would like to
> know
> if it is advisable to do that, and if so would you test between the
> grid
> and anode? I hear the grids are pretty fragile.
>
> Any further ideas? Also, if anybody has a socket and/or chimney
> system
> available for the 8877, I would be building a single holer so would
> appreciate knowing what's out there. Contact me off list on that.
>
> As always, any info much appreciated.
>
> 73 Kevin K7ZS
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|