[HATS] Re: 400 watt solid state class A broadband (400-900 Mhz) AMPS 4 SALE

[A9xw@cs.com]

After configuring the transmitter, I wound up with 6 bricks, no complete 
blocks. Each amp is up to 150 watts output, class A, no tune, broadband, 
operates on 26 volts. Make sure no spikes or over voltage from the supply at 
turn on. usually best to turnon the supply, then a second switch for the DC 
if you're not sure. Each amp has 4 devices in push pull parallel. Internal 
phasing and matching and internal bias, no external bias supply needed.  Type 
N connectors in and out. 
Each amp is about a foot high, (sits vertical in a transmitter) about 20 
inches long and 4 inches wide.  Its a massive heat sink. Considering these 
things are rated to run forever it is over built for ham use.  There is a 
DB15 connector on the front that can be used to monitor the output and other 
parameters of each device!  Max broadcast drive is 20 watts. typically 15 
watts for 100 out. There is thermal protection and a front panel LED if you 
heat trip.  There is a green LED (six total) one fore each of the 4 devices, 
two for power, a yellow for WARM, and a red for overload.  A lot more than 
your average Mirage amp!  Any decent fan should keep it cool. The cooling 
must be on all the fins, not one area as the power divices are spread out and 
not concentrated in one end as ham amps are. 
When the unit is in a transmitter, it sits vertical with the cooling blowing 
from the bottom to the top (across the direction of the heat sink fins, not 
at the heat sink fins.  These particular modules were on channel 60 and 62. 
it is quite likely they will work for 900 Mhz as well, but not tested there.  
Not necessary but recommended is the use of a simple circulator to keep 
antenna VSWR problems from causing problems. Do not run into an open or 
short. This is class A, it puts out power all the time there is RF input. 
There is internal VSWR protection, but the devices are about $200 each, so 
you do not want to blow one! 
I have one three port combiner, two are needed, but you can copy the PCB and 
make your own if you want to combine them.  Its a simple transmission line 
impedance transformer using the foil width to change the impedance.  There 
are no frequency selective components in the amps. They are broadband. These 
were made by Comark, and are about 10 years old.  I can supply a schematic as 
i have a set of books for this vintage transmitter. 

Considering I dont have the brick frames, these are "loose" as a D1010 etc,  
I would accept $300 per module. 

73

Henry AA9XW
 
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