[Boatanchors] Replacing 866s with 3B28s

[WQ9E at btsnetworks.net]

Bill,

I built solid state replacements for the 866 tubes in my Valiant and 
Valiant II but if you want to stay with tubes the 3B28 is a better 
choice than the original MV tubes.  You don't need an additional dropping resistor when replacing MV tubes with SS because the voltage drop is also very low with MV tubes.

If your Valiant is early production, check the wiring between the LV 
transformer and the 866 cathodes.  This winding has the full HV on it 
and the early Valiants were built with standard hookup wire that tended 
to arc and short taking out the LV transformer in the process.  If the 
insulation on these wires is not obviously thicker than the standard 
wiring either replace it with proper HV wire or sleeve it.

Rodger WQ9E

----------------------------------------
From: bill kipping <ke7kk at earthlink.net>
Sent: Wednesday, December 29, 2010 2:22 PM
To: boatanchors at mailman.qth.net
Subject: [Boatanchors] Replacing 866s with 3B28s 

Hi to the group.  I want to replace the 866 rectifiers in the Johnson Valiant with 3B28s (blue tubes are scary!). Any thoughts or experiences pro or con. TNX Bill

New Years wish to all, may Washington DC stay out your lives and wallets in the new year.   
______________________________________________________________
Boatanchors mailing list
Home: http://mailman.qth.net/mailman/listinfo/boatanchors
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Boatanchors at mailman.qth.net

List Administrator: Duane Fischer, W8DBF
** For Assistance: dfischer at usol.com ** 

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html