I have added a direct-to-output track N-type (on standoffs), fitted a SMA input socket, removed the input attenuator, bypassed the first stage (DOA or soon after), replaced the 10R bias resistors, added a bit of snow-flaking and removed both intermediate circulators. According to my measurements, it delivers about 42 watts of RF, more may be available with skilled snowflake tuning. Be aware however, the final devices are not designed for 2.4 and are pretty inefficient. It soaks up at least 12 amps at 28 volts.....That said, I was nearly able to match the beacon on 333kS at the end of 10m of 4-500 and 1m of RG402 semi-rigid. I drive it with the little AMSAT amplifier with the built in SAW filter https://shop.amsat-uk.org/Filtered_S_Ba ... 51527.aspx. More drive may give you more RF but I think its probably enough as-is.
It uses a lot of DC at 28 volts and it gets warm. The fan is a mains powered unit of suitable spec. and by ducting it the heatsink (which was never designed to dissipate this much heat) maintains a safe operating temp. By partly blanking the outlet fins over the input stage (which doesn't get hot), greater airflow is produced over the hot bits and it all stays under control.
I have built a replacement amp now using a different pallet so this unit is now surplus.
Its certainly good enough to get you going and would be a lot more economical (but no more efficient) on the NB section.
A spare XT60 power plug will be supplied with the amp for you to wire up. There are short pigtails on the back of the power input if you want to use a 12 or 28V fan (which I did originally, but have since re-used in my new amp). More photos available by email showing insides etc.
£125 + £5 UK delivery. Private Message me if you are interested. I will ship to the EU but potential costs to both of us may render it unrealistic.
In the following article, towards the end, extensive details are shown about its potential performance. https://dd0yr.de/Bilder/13cm-PA/13cmPowerPa.pdf It certainly seems possible to 'tweak it up'....
Gareth
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