I repaired the TL-922 of a friend in 2006.
One of the tubes had a grid short and the heater transformer was meltet.
After repair I ordered a matched pair of 3-500ZG from RFP.
They did very good gain from the beginning and got red equally with a dead
carrier.
Since then the amplifier works perfectly well on all bands, my friend is
quite active
73
Peter
-----Original Message-----
From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com] On
Behalf Of ALEX AIMETTE
Sent: Freitag, 21. Dezember 2007 19:11
To: AMPS
Subject: [Amps] FYINFO--3-500z PROBLEM
I AM POSTING THIS FOR YOUR COMMENTS AND INFO. i HAVE HEARD THAT AMERITRON
HAS HAD A PROBLEM--NO PERSWONAL KNOWLEDGE!!!!
ALEX W2OX
-------- Original Message --------
Subject: Re: [FRC] Eimac 3-500Z tube
Date: Thu, 20 Dec 2007 21:24:35 -0500
From: fainsbert <cmfainsbert@verizon.net>
To: <frc@gofrc.org>, <bob@applegate.org>
References: <200712210145.lBL1jYml029354@buzz.applegate.org>
Bob:
Thanks for your almost instantaneous response. I did buy two matched RF
Parts 3-500ZG's. And that may be part of the problem!
I have an old Henry 2K Classic X amp and in the SSB position, it runs at
about 3800 volts key down and 800 ma. Theoretically, that's within the 3-500
specs.
I did insert the RF Parts 3-500ZG tubes in the Henry and it appeared to run
perfectly until I had a extended QSO [10 minutes] and both tubes began to
oscillate and glow cherry red. This same thing started to happen more
frequently destroying some of the amps internal components. I sent the tubes
back to RF Parts [they were still under warranty] and they tested OK.
Finally, with the efforts of NO2R, the Henry was "revitalized" and the RF
Parts tubes were reinserted. Within 10 minutes into a QSO, the oscillating
repeated itself. The Henry was turned off and the RF Parts tubes were
removed and replaced with a pair of used Eimac 3-500Z's.
I have my suspicions that the RF Parts 3-500's may work fine under a lower
plate voltage lower than 3800 v. Made in China? Maybe they used inferior
internal parts to save a few pennies.
I have had this Henry for over 20 years and it helped me with 337 of my 338
[ yes, even FJ] DXCC contacts.
Oh yes, I also have a QRO HF-2500DX.
I love my Henry!!!!!
Best Wishes to all for the Holiday Season/
Chuck Fainsbert
KC2NB
----- Original Message -----
From: "Bob Applegate" <bob@applegate.org>
To: "fainsbert" <cmfainsbert@verizon.net>
Sent: Thursday, December 20, 2007 8:45 PM
Subject: Re: [FRC] Eimac 3-500Z tube
> RF Parts has really good 3-500ZGs; I've used them for a number of contests
> in my
> amp with great luck, despite lots of REALLY BAD things being done to them!
>
> 73
>
> Bob - K2UT
>
>
>
> Fainsbert <cmfainsbert@verizon.net> wrote :
>
>> Does anyone have a new Eimac 3-500Z tube that they
>> would like to sell?
>>
>> If so, please email to
>
> ___________________________________
> NOCC, http://nocc.sourceforge.net
>
>
>
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