[600MRG] Loudenboomer PA junk...

[Edward R Cole]

Definite overkill.  Only 100w is needed with 5% efficient 
antenna.  6146, 807, ...all 1950's technology and construction.

73, Ed
5w max EIRP for 630m ham band

At 08:31 AM 1/26/2018, Dave Riley wrote:
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>Heathkit SB600  'rework' Dave Riley, AA1A
>
>On 1/26/2018 11:59 AM, Edward R Cole wrote:
>>Want a cheap high power amp?  Modify a stereo amp by removing audio 
>>transformers and audio bypasses with 0.1 uF.  I'm told the power 
>>transistors are able to run at 500-KHz.
>
>Or throw your grapling hook in to the junk pile and 'Golly Gee' a 
>simple old broken down Heathkit SB200 yet...
>
>1. Buy/install a new face plate on ebay, DONE
>2. Rework remove input switches and L/Cs to a single band ( 630m ) 
>cathode input, tuned and DONE
>3. Install aftermarket step start and external relay mods, DONE
>4. Rework output band switching by removing most of it, DONE
>5. Install 'external' plate tuning circuit, keep DC to ZERO VOLTS 
>outside of the case please, or you are DONE
>
>It was my WD2XSH/17 summer project in 08 and was needed to make 20W 
>erp... It was more than adequate...
>Hummm, maybe it needs to go on 2200m now...  Not done...
>
>Anyway the filaments in this blunderbus are too expensive compared 
>to a low volume air fan on to a pair of IRF460s built in to a 
>surplus Mitsubishu A7DC chassis..
>Idle signal state = NO CHARGE...
>
><http://www.radiocom.net/600M/SB600M2.jpg>http://www.radiocom.net/600M/SB600M2.jpg
>http://www.radiocom.net/600M/SB600M3.jpg
>
>Regards from TinkerDave @ aa1a     Got Junk??
>
>
>
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73, Ed - KL7UW
   http://www.kl7uw.com
Dubus-NA Business mail:
   dubususa at gmail.com 
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