[Johnson] Valiant I crystal oscillator won't unkey

[Rodger]

Al,

The addition of inrush current limiters to the LV and plate supplies 
will take care of the fuse blowing and reduce the stress on the 
transformers; around $3 for both from Mouser.  The only thing you lose 
is that classic "bong sound" from the plate transformer being energized. 

I have a soft spot for the Valiant since it was my original novice rig 
in '75.  I have 2 of them now and both have the original audio 
circuitry.  I am convinced that a lot of the Valiant audio trouble is 
due to owners who didn't read the manual carefully and turned the 
clipper control to full CCW which, intuitively, is minimum.  Of course 
that is actually maximum clipping and sounds bad; as you know turning 
full CW removes all clipping.  There are plenty of times where a little 
clipping helps a lot with weak signals-HiFi AM isn't much good when you 
cannot copy it through the noise and interference.  I also restored my 
Viking 500 to its original audio and on a couple of occasions I have 
dialed in a little clipping to help out the receive operator. 

I assume you did check or replace the filament wiring to the 866A tubes 
(or disconnected it if you have replaced with SS).  Intermittent fuse 
blowing is one of the symptoms of this flashover.  When I got into 
vintage gear in 1994 in an effort to recreate my novice setup the first 
thing I bought was a Valiant and a parts unit.  The parts unit had a bad 
LV transformer due to the 866A filament lead problem.

Hope to work you and your Valiant sometime Al!

73, Rodger WQ9E

Al Parker wrote:
> Good AM Roy,
>    My Valiant developed the same problem this weekend, I'd love to 
> have your notes.
>    I hadn't used it since last Spring I guess, and figured it was time 
> to get back on 160m at the end of last wk, so I powered it up.  about 
> a minute into things, the fuse in the pri. of the LV xfmr failed, it's 
> the one inside, of course.  It's so much fun horsing that thing in & 
> out of the case & up on end.  Didn't find any problem, so put in 
> another fuse (it really needs a slo-blow) and then had the osc. 
> problem.  Figured it had to be something flakey like screwy ground 
> connx or some such, so started unplugging things.  After I pulled the 
> RF in & out cables from the SB-10, it cleared up.  No reason for that, 
> but I didnt' chase it down, just went ahead to get the other things 
> ckd out.  But later realised that teh mod. idle curent is high, so 
> need to get back into it.
>    I have been thru the Valiant, last yr after I got it, and replaced 
> all the electrlytics, etc., so it should be OK in that respect.  I 
> ddin't do the sometimes suggested/recommended audio mods.  I'd done 
> them in a Viking 1 a cupla yrs ago & it was very nice, I just wanted 
> to see how the Valiant would sound, it is a bit different.  Haven't 
> had any adverse comments.
> tnx, 73,
> Al, W8UT
>
> ----- Original Message ----- From: "Roy Morgan" <k1lky at earthlink.net>
> To: "Paul Carreiro, N6EV" <N6EV at MonteCarloSS.com>
> Cc: <johnson at mailman.qth.net>
> Sent: Tuesday, December 16, 2008 8:55 AM
> Subject: Re: [Johnson] Valiant I crystal oscillator won't unkey
>
>
>>
>> On Dec 16, 2008, at 12:47 AM, Paul Carreiro, N6EV wrote:
>>
>>> Greetings..
>>> ...  The crystal oscillator (C1/C2 switch position) doesn't unkey  
>>> when the key is not closed.
>>
>> Paul,
>>
>> This is a known problem.  Roger in a reply message mentions "the  
>> keying modification".  I can't remember what that is, but:
>>
>> I will send separately my notes file on the Valiant to you - the  
>> problem may well be in there somewhere.  I have not looked into it  
>> yet. I seem to remember this trouble being mentioned before here on  
>> the list.
>>
>> Roy
>>
>> Roy Morgan
>> k1lky at earthlink.net
>> 529 Cobb St.
>> Groton NY, 13073
>>
>>
>>
>>
>>
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