Swan Mk-6 ? Vs. Mk-6-B

[K3JVB]

Hello all

Can anybody tell me what the difference is ...

Swan "Mk-6" vs. "Mk-6-B"?
Thanks
John
k3jvb

[W1QJ]

John, I am not really sure, but I can take a shot at it.  I think the earlier Mark VI's like the earlier Mark II's had 3-400 tubes.  Like the Mark II's, they switched to 3-500;s and added bias.  The thing is with the Mark II's they did not change the model name/number even though they made some major changes.  The earlier Swan mark II's had a wimpy tank circuit whereas the later ones were beefed up a bit.  But I could be all wrong about this holding true with the MArk VI, but it could be true too.  Not sure.
Lou

[K3JVB]

Hi again Lou..

Yes the one I am looking at is the "B". I also have a early MK-2, with 3-400-z tubes dated (4-17-1965)
They still put out full power plus...

The tank circut in mine looks pretty much the same as the 3-500-z units, but there are some differences in the schematic, and the power supply.

Good to se ya again ! )
73

[AA4ZZ]

As I recall the Swan Mark 6 is the 50mhz model of the HF Mark I which has an internal power supply. The Mark 6B is the 50mhz version of the HF Mark II which has a seperate power supply. See these HF amps at the Virtual Swan Museum:
 http://www.pcs.mb.ca/~standard

So physically thye are very different. I have a Mark 6B. I have never seen a Mark 6.