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Old October 31st 05, 02:06 AM
Uncle Peter
 
Posts: n/a
Default Old Xmtrs, "Ancient Modulation" and Amps


"Lazy Senior" wrote in message
newsse9f.3726$zT6.3512@trnddc06...
I recently acquired a Viking Ranger in nice working condx.

I am interested in using this on AM on 160, 80, and 40 mtrs. The Ranger
runs around 40 watts Am carrier output. I would like to get an amplifier
to use with this xmtr, maybe a vintage amp. What should I be looking
for? I would like to run legal Am Limit on these 3 bands. Should I
forget about Vintage Amps and get a modern Amp? Suggestions please. Any
pitfalls to using a modern Amp?

Thanx

Lazy Senior


This is not as easy as it seems. AM peak power is
4 times the carrier. A 100% modulated 40 watt AM
signal is actually producing 160 watts PEP.
The linear amplifier could only be driven to about
25% output on an unmodulated carrier from an AM transmitter,
otherwise it would be severely overdriven on modulation peaks.
If you could drive a linear to 1000 watts, the maximum carrier
power for AM would require the drive to be set for about 250
watts max.

If you want more power you could drive a class C amplifier, and
apply high level modulation directly to it. Trying to "amplify" an
AM signal is very, very inefficient and difficult to set up properly.

Pete