[NLRS] Repeater amplifiers for SSB?

[Dr. Gerald N. Johnson]

On 8/4/2016 5:35 PM, Doug Reed wrote:
>
>
> My opinion is that you could probably linearize an old vacuum tube FM
> amplifier much easier than you could a transistor amp. Although
> finding one of the old GE MASTR Pro 330W amps that used a 4CX250 might
> be a little hard these days.... With the old Class C transistor FM
> amps having multiple parallel finals, I wouldn't even want to attempt
> biasing them.... Go with something modern instead.
>
> Motorola often went in for odd-ball conduction-cooled power tubes.
> They usually had beryllium for the heat sink insulator so they were
> treated as hazardous waste. I can get you one of those up in Little
> Falls, MN if you want to pick it up..... It is still in a Motorola
> Motrac vintage FM repeater in a 6 foot rack.... Probably no more than
> 150W RF out.   :-)

Actually its beryllia, beryllium oxide ceramic. A better heat conductor 
than solid aluminum Also often used in RF power transistor cases. 
Contact or ingestion of beryllium or compounds has been proven to cause 
cancer. So long as its not powdered and stays solid it appears to be 
safe. Many RF power transistor data sheets include warnings about 
cracking the beryllia.

73, Jerry, K0CQ
>
> 73, Doug Reed, N0NAS.
> ______________________________________________________________
> NLRS mailing list
> Home: http://mailman.qth.net/mailman/listinfo/nlrs
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:NLRS at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>