Multiple 110w A9 Spectra's with no TX power

[007]

Time for the off-the-wall problem of the month:

I have 4 high power A9 VHF Spectra's, all of which has this same problem: They RX great but all have TX power between 0-20mW. I can't see any visible cap leakage, checked all the RF jumpers inside etc but nothing helped. The environment they are used in is/was mobile, in my vehicle. Antenna is a decklid NMO with about 7 feet of the low-loss white RG58 that Antenex uses. Every time I've installed one of these trays into the car, they either don't have TX right away or they lose it shortly after install. Power is a 6ga to the trunk from the battery thru a 100a circuit breaker under the hood and a fuse in the trunk.

I have a 45w A4 and A9 that use the same antenna, power source and cable set with zero issues over 5 years, but every time I try and install a 110w tray it fails. The trays are from different sources over the last few years, and all worked 100% before I got my hands on them.

Thoughts? Are they being fussy about some part of the mobile install or are these all just bad trays? The A9 head causing an issue? I'm out of ideas...

[akardam]

Just out of curiosity have you thrown an ampmeter on the line feeding the high power radio and seen what it's actually drawing (before one gets cooked if you have the opportunity and certianly with one of the bad drawers)?

[mancow]

I have one like that too that's driving me nuts. This happened once before and it was an open solder joint on a coil in RF deck. However, I replaced the entire RF amp deck on this one and nothing changed.