[Amps] SB-220 on 6 meters: looking for projects...

[Han Higasa]

http://www.iizuka-net.ne.jp/~bear-el/sb-220-6m/

Translated some comments at the page. JA6TAY wrote:

In Japan SB-220 is rare, on this time I will modify it to six meters.
In operation SB-220 is as same as TL-922 or HL-2K with two 3-500Zs.

This SB-220 has its priary voltage configured to AC 100V.
So the plate voltage will down to 2.4 kV at full power.
The power transformer is a bit small, so I obtained about 800W out
at 50W drive. I can obtain nearly 1kW but I feel it is dangerous.

Some comments of each photo:
Remove all the things not required for six meter operation.
Need to change antenna relay to another one.
One turn coils for parasitic-suppressors.
1000 pF plate stopping capacitor.
This time I used pi-l plate circuit.
Need a large plate coil; it should be tuned correctly at the same time
such as this photo.
Need to modify a plate RFC for six meter.
Need correct grounding of VCs by thick copper ribbons.
Exchanged an antenna relay and moved its place.
I used a troid-core (seemingly T-68-10 or T-50-10) for input pi-circuit.
Ground all the grid terminals by means of ring wires.(I = Han used here
copper 'C' belts instead of ring wires here around the socket pins)

GL, de Han JE1BMJ

----- Original Message ----- 
From: "Han Higasa" <higasa at plum.ocn.ne.jp>
To: <Amps at contesting.com>
Sent: Monday, February 11, 2008 2:55 PM
Subject: Re: [Amps] SB-220 on 6 meters: looking for projects...


> Joe
> I forgot a link of SB-220 for six.
> 
> http://www.iizuka-net.ne.jp/~bear-el/sb-220-6m/
> 
> GL, de Han JE1BMJ
> 
>