[Boatanchors] Front panel for Viking Valiant needed

[WQ9E at btsnetworks.net]

I always mount the replacement resistor back in the VFO and I find that the drift stabilizes fairly quickly.  Although there are a lot of heat generating parts in the Valiant, it is large and is well ventilated thus the temperature varies a lot between transmit and receive, especially with lengthy transmissions on AM. 

The Ranger has a lot of stuff packed into a small box and given the design (no separate plate transformer so plate voltage is always present) it tends to run very warm at all times so I imagine with the resistor mounted externally in a Ranger it would be slower to stabilize (than internal mount) but at least it probably wouldn't vary a lot between transmit and receive conditions.

In any case, a properly sized resistor works well inside the VFO.  If the previous resistor was bad consider replacing the VR tube since it may have taken a beating and the regulating ability can deteriorate.

I have found that the VFO in my Viking 500 stabilizes very quickly but this is based upon a sample size of one.  I have a couple of Valiant 1, a Valiant II, Pacemaker, Ranger 1 and Ranger 2 for comparison but only 1 Viking 500. It would be interesting to hear of others experience with the Viking 500.  Unfortunately the Viking 500 didn't come with the VFO output connection (like the Valiant) so I cannot easily hook my Johnson SSB adapter to it; otherwise it would be preferable to the Valiant for vintage SSB use.

Rodger WQ9E



-------- Original Message --------
> From: Glen Zook <gzook at yahoo.com>
> Sent: Monday, November 07, 2011 9:55 AM
> To: Paul Baldock <paul at paulbaldock.com>, "boatanchors at mailman.qth.net" <boatanchors at mailman.qth.net>
> Subject: Re: [Boatanchors] Front panel for Viking Valiant needed
> 
> Several years ago someone actually did some experiments on several Johnson Ranger and Valiant transmitters with the resistor in and out of the VFO chamber.  The conclusion was that with the resistor in the chamber the VFO stabilized much faster, sometimes when the resistor was outside, the VFO never stabilized.  The supposition was that the temperature compensation relied on the heat from the resistor.
>  
> Glen, K9STH
>