AMT High power transmitters
fgr@st-andrews.ac.uk
Wed, 2 Mar 94 14:53:06 GMT
Recently we had a major and very expensive breakdown of the AMT
M3200 high power transmitter on our MSL 500. Two of the transistors in
the M3000 power supply went short circuit. This increased the output
voltage from a nominal 28v to over 60v. Disatrous consequences were
experienced throughout the transmitter which had to be returned to the USA
for repair. We had 5 months working with a jury-rigged 500 watt amplifier
supplied by our physics department.
There appears to be no protection in the AMT power supply to guard
against this. Indeed, the protection circuits appear very limited. We
recommend users to insert themselves a protection circuit to cut off the
mains power if the output voltage goes over (say) 32 volts (our best
guess). It could save you a lot of lolly!!!
Greetings to you all from a spring-like (at last!) St Andrews by the sea.
Frank Riddell