[Johnson] Viking I durability?

[Carl]

The driver iron limits the modulation % well below 100% without serious 
distortion while the mod transformer is stressed much beyond 100% at 100W as 
it was designed for the lower power V-1. Raising the HV, changing to higher 
output tubes, etc is asking for trouble in either TX.

The Heath DX-100 mod xfmr can be substituted, there appear to be plenty 
available.

Carl
KM1H


----- Original Message ----- 
From: <tbs50a at aol.com>
To: <johnson at mailman.qth.net>
Sent: Saturday, May 25, 2013 4:46 PM
Subject: Re: [Johnson] Viking I durability?


>
> From what I've seen the driver transformer is the problem not the mod 
> trans. The large voltage divider resistor is usually open. The LV power 
> trans sometimes fail.Be careful with the V1 w/829B. It has no clamp tube 
> (along with the early V2's) tuning it up with no or low grid drive will 
> kill the 829B in a flash.These are a few things right on the top i can 
> think of.
> Terry N3GTE
>
>
>
>
>
> -----Original Message-----
> From: Brian Burns <brian at lessonsinlutherie.com>
> To: johnson <johnson at mailman.qth.net>
> Sent: Sat, May 25, 2013 2:08 pm
> Subject: [Johnson] Viking I durability?
>
>
> Hello Carl,
>
>
>
> " OTOH the V-1 didn't age well and survivability percentage is likely 
> lower.
> It was already a throwaway by the time the late 50's SS gear revolution
> hit."
>
>
>
> I've heard that the modulation transformers weren't quite up to the job, 
> but
> otherwise they seem to have a really good reputation for reliability. What
> other issues are there, that might be fixed in a restoration job?
>
>
>
> Thanks,
>
>
>
> Brian
>
>
>
>
>
> ______________________________________________________________
> Johnson mailing list
> Home: http://mailman.qth.net/mailman/listinfo/johnson
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Johnson at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>
> ______________________________________________________________
> Johnson mailing list
> Home: http://mailman.qth.net/mailman/listinfo/johnson
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Johnson at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 10.0.1432 / Virus Database: 3184/5854 - Release Date: 05/24/13
>