I went down/up to the repeater site today, and made the following changes:
- Added a RF Concepts RFC-2-317 amplifier to the transmitter
- Added an Advanced Receiver Research P144VDG Receiver Preamp
- Added a Wacom Bandpass filter in the receive path
- Added a Wacom Bandpass filter to the transmit path
- Added a 12 VDC power supply for the amps
The bandpass filters were previously installed at the Xerox Tower site.
Mike Ishler KE2LU donated the RF Concepts amplifier. Thanks Mike!
I had no serious test equipment, but everything seemed to be working.
The repeater is set to 20 watts, and according to my MFJ VHF Wattmeter/SWR meter, the amplifier is putting out around 80 watts. The amp is not designed for repeater duty, but we are only running it about half rated power. It has temperature protection, but I want to get a fan on it.
Initial reports are good. I’ve had a few QSOs, including one with Harry W2HRY, just using an HT in my shack at home, about 39 miles from the repeater. On my 2 meter mobile in my shack, it went from 1/2 scale on the s-meter to one notch from full scale.
Mike W2HYP had no trouble using an HT from the U of R just after I made the changes.
The addition of the preamp changed the squelch action, so I did my best picking the right level. The squelch has always been questionable, so additional tweaking may be necessary, including an internal “threshold” adjustment.
If you get a chance, see how it is working for you, especially if you had some problem areas where it was marginal. If things seem to be good, Fred Miller WO2P has agreed to help package things up in the repeater cabinet.