Has anyone seen any mods that would add a Bias-Tee feature to older receivers (non-SDR)? I'd like to enable my R-7000 to power an antenna mounted preamp.
Why don't you just use a bias-T injection block. That way you don't have to tear into the radio. Just use a coax cable between the receiver and the injection block. If you change radios, you just move the injection block to the new radio. It's done all the time in commercial and public safety radio systems.Has anyone seen any mods that would add a Bias-Tee feature to older receivers (non-SDR)? I'd like to enable my R-7000 to power an antenna mounted preamp.
And that is why I keep a box of 100 and 200ma 12vdc wall wart power supplies around, antenna related, computer interfaces and modem TNC devices get transformer isolated non switching power supplies, not everything gets hooked up to the Astron RS-70MTrying to avoid adding more switching power supplies.
You don't need any special test equipment to replace those parts. A DVM might be handy to check voltages and such.If I had the equipment to do all of that, I would. The local Icom (commercial) radio shop said they would have to send the R7000 to Icom. Icom has been declining to service their discontinued equipment lately, so I told them not to bother. Besides, the shipping would probably cost more than the repairs.
I think a preamp would be sufficient to overcome the sensitivity loss. I'm not having any of the other problems. If they should appear, then I will scrap the receiver.