[Amps] Peter Dahl / Harbach SB-220 transformer

[Carl]

> Date: Sat, 12 Jun 2010 07:03:51 EDT
> From: Gudguyham at aol.com
> Subject: Re: [Amps] Peter Dahl / Harbach SB-220 transformer
> :
>
>
>
>
> ##  A buddy across town   built a single 3-500z  for 6m.. works good... 
> abt
> 500w .   He  wiped out the neighbourhood
> CATV... and that amp was relegated to FD  use.  He also wiped out the 49.9
> mhz  cordless phone freqs at the  time.  This
> was 10 yrs ago.
>
> ***** Well, if it only made 500 watts nothing was tuned right, there is
> still another 500 watts in there.  Tune it right and you'll get the power 
> in
> the right place not on cordless phones and CATV.
>
> ####  That was a HB  SINGLE  3-500Z  6m RF deck.    The tube was
> semi flat.. and he had 100 w icon to drive it.    500w  from a flat
> 3-500Z is not too bad.
>
> ## the amp was tuned correctly, LP filters, shorted 1/4 wave stubs et all.
> The problem is... you stuff 500 W  into a 5 over 5 stacked array... and 
> it's
> always gonna be pointed at one or more neighbours homes.   Back then, 
> those
> baby monitor's could be heard [across the street]  on 49.990 mhz.   I 
> doubt those
> things will reject the low end of 6m.   Ch-2 TV is another similar 
> problem... none of em
> have HP filters in em... and bye-bye ch-2.   Then toss in the 49 mhz 
> cordless phone band.
> Do those things cut of 6m ??
>
> No wonder he wiped out the neighbourhood.   I looked around my 
> neighbourhood... and dumped
> the notion of installing the 9-el  6m yagi.[+ 2 kw]   A buddy 1 mile away 
> is up on a ledge/hilltop.   At the
> time his icom had 6m.   He installed an inverted vee on his flat roof... 
> abt 10'  above the roof.
> [and 400' ASL]  ..with no balun.. and fed with 80' ofr RG-58.    One 
> afternoon... the 6m band was
> hopping. He had a 3 hr pile up into the east coast.. with lots of 60 over 
> S-9 sigs in both directions.
> Then the band went dead.   He stayed dead for months.   His next rig did 
> not have 6m .
> That was his 1st and last 6m experience.
>
> if I had more room.. 6m might  be an option... but as is... I have no room 
> for 10/12m.
>
> Later.... Jim   VE7RF


Some years ago I had another ham call and tell me I was interfering with his 
baby monitor and he was able to identify my call on CW. He was about 18 
miles away. He wasnt upset, just very surprised. I was on 6M with 1200W 
working Africa and beaming in his direction.

Carl
KM1H