Recent News & Updates:
I built a serial interface for the computer to directly key up the repeater, and it's working pretty well.
mid-August: we have the repeater on the Echolink system now. Our node number is 127188, and it should be up pretty much full time.
August: I have the main transmitter on a UPS now
in April: bought a notch filter for the VHF pager band for the receiver...now it doesn't squeal anymore.
Sometime in Feb. 03: made a box out of tin foil to put the VHF controller and UHF receiver in...helps keep stray RF out of everything...and it looks way cool.
12-23: cut off excess length of coax at receive site and reterminated coax, checked SWR, lookin' good.
10-?: had a late night stroke of genious and realized that I had a capacitor in the wrong place on the VHF side controller...took that out - made much better transmit audio, and now we can use whatever UHF RX scanner we need to, without that crazy distortion problem.
september: mostly just sat around on our rear ends, and ate at subway.
8-16: added UPS battery backup to receive side of repeater
7-?: mounted repeater in square-D box, added additional cooling fans
7-?: took down 40' tower and J-Pole, raised 70' pole, mounted new J-Pole
7-?: reinforced new J-Pole antenna; possibly the best antenna we've made yet
7-?: made new dual-band J-Pole for receive site
6-?: put Pro-51 back on UHF receive because Pro-44 picked up 460.550 police frequency
6-?: tried using Pro-44 scanner for UHF receive at Ian's
4-?: mounted J-Pole back up on Ian's tower
4-?: reconditioned Ian's J-Pole for use as repeater backup / voice / packet antenna
4-?: removed Ian's J-Pole from transmitter site
3-27: mounted UHF receive 5-element Yagi on Ian's tower
3-26: raised and mounted 40 feet of pole, with J-Pole on top. Added cooling fan to transmitter.
3-25: attached 20 feet of pole to the red van, with J-Pole on top, put repeater on air
3-24: worked on receive J-Pole some more
3-19: got dual-band J-Pole built & tuned out for receive side
How it Works
The receive side of the repeater is a dual-band Standard handheld, attached to a homebrew dual-band J-pole, about 75 feet up. This radio recieves 147.840 MHz, with a tone of 186.2hz, and retransmits the signal on UHF. This signal is then picked up by a 5-element yagi 30 feet up about 1½ miles away, attached to a Pro-51 scanner. The scanner feeds a VOX unit (two 741 op-amp's, and some other components), which activates the Yaesu FT-2500m transmitter on 147.240 MHz. This radio is currently putting out 25 watts into an MFJ dual 5/8 wave vertical, about 65 feet in the air.
The repeater covers the Thomasville city limits nicely, and provides excellent handheld coverage in the downtown area. All liscensed amateurs are invited and encouraged to use this homebrew project at any time.
and one day, when Jared comes back from Dixie, we may even have an autopatch. (hah!)
Special Thanks
....goes out to: KG4PUY, KG4PUZ, KE4URL, KF4CLE, KG4GAV, and KI4AWK for their donations of time, energy, brainpower, NMO mounts, laughter, candy, money, propane, bagphones, and all the stuff that has to be had to make a repeater work to this project. Also thanks to TARC for their continued support and laughter.
-73 de KF4AON
