Amps
[Top] [All Lists]

[AMPS] SB-220 conundrum

To: <amps@contesting.com>
Subject: [AMPS] SB-220 conundrum
From: measures@vcnet.com (measures)
Date: Wed, 19 Jan 2000 16:37:06 -0700
>
>Howdy Pete N4ZR and Amp nuts -
>
>I have heard that you can test for VHF parasitics by disconnecting the RF
>input and RF output from your amp and then, with the relay closed (ie, HV
>etc. applied)watch the plate and grid current meters while rotating the
>plate and load controls.
>
>I can see how that would work in some cases but don't know about all cases.
>
I can not see how this stability test would work at frequencies higher 
than HF.  .  To start the most destructive type of parasite (intermittent 
vhf push-push) , a rapid change in anode current is needed.  This 
requirement can be met by switching ZSAC either on or off.  Sometimes a 
vhf parasite can be started by sending high-speed dits.  

later, Lu

-  Rich..., 805.386.3734, www.vcnet.com/measures.  


--
FAQ on WWW:               http://www.contesting.com/ampsfaq.html
Submissions:              amps@contesting.com
Administrative requests:  amps-REQUEST@contesting.com
Problems:                 owner-amps@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm


<Prev in Thread] Current Thread [Next in Thread>