NEW!! 33cm Repeater!!
927.0125/ input 902.0125 pl 100, soon to be on echolink!
Plans of linking most of Northern CA all on 900!
Here's a map of future sites.
The KJ6KO/R 927.0125 repeater is located near El Dorado Hills, CA at about 1400'. It is an open repeater and all are welcome. It was put up with donations from local HAM's as an alternative to UHF which is being killed by the USAF due to interference to their PAVE/PAWS/UEWS system at Beale AFB. Over 150 UHF repeaters were required to either go off the air or drastically reduce ERP in the direction of the AFB.
The 927 repeater consists of a Motorola MAXTRAC 900MHz radio as a receiver and a Motorola GTX 900 MHz radio as a transmitter. The Maxtrac has had extensive modifications for use as a receiver and the GTX is stock except for power output reduction to 1.3W. It drives a surplus cellular amplifier to 50W TX power. It also uses a surplus cellular duplexer retuned for 900MHZ. There is also an additional bandpass filter on the receiver and a single channel bandpass cavity on the transmitter. Power to the antenna is 30W. Antenna is a 9dbd omni. Receive sensitivity is 0.17uV @ 20db quieting thanks to an N6CA PHEMT preamp! Coverage is very good in the Sacramento valley from Marysville south to Stockton and only slightly worse than an equivelant UHF repeater would be in the same location. Controller is a Link Comm RLC-1. We hope to get an Echolink connection soon!
Plans are underway to add FOUR more 900 repeaters to link most of Northern CA together on 900 MHz!!! See the map above. The plan is to cover a lot of rural areas of the state (SF excluded) and still keep the traffic down. We don't want this to become another "Condor" or "WIN" system, just a bunch of "real" hams rag chewing about "real" stuff like amplifiers, antennas, weak signal VHF/UHF/MW etc!!
If you would like to donate to the cause, donations are graciously accepted!
Paypal is the easiest way. Donate to..... firstname.lastname@example.org.
Thanks to the following for miscellaneous donations such as antennas, cash, controllers etc.!!
WA6KTK, WA6ZKY, N6JV, KI6SSF, W6OMF
The 900MHz band is a MESS in most metropolitan areas due to Part-15 cordless phones, baby monitors etc, so the repeater does transmit PL also for decode. There is a ton of Part 15 garbage and some of it makes it's way into the repeater uplink area of the band. There is some sort of high power system in the Sacramento area that we are trying to track down. Part-15 devices are LIMITED to 1W EIRP so we should not be hearing it from 25 miles away from Sac at -80dbm! Fortunately, the bottom of the band is pretty quiet, so we took the bottom repeater channel with hopes to "clear the air" later for other 900 repeaters later down the road. Good news! I have confirmed with the ARRL and FCC that licensed amateurs DO have the right to get rid of any interference from Part-15 devices! There is also licensed services between 902 & 928 (Part 18 & Part 90) that are capable of running as much as 300W, but there are no licenses granted in the Sacramento area on anything between 902 & 903 so the airwaves should be clear.
For info on modifying MAXTRAC and GTX radios for use on the 900 MHz ham bands, look
HERE FOR GTX Info and HERE FOR MAXTRAC Info. Also HERE FOR TONS OF MOTOROLA INFO
Remote base and repeater system.
(Placerville)440.700 pl 123, 2m all mode remote base, linked to .450.
(Sacramento Valley)441.450 pl 100, linked to .700.
Again, all these pages will have more info later.....
The remote base is located in Placerville with an elevation of about 2500'. The remote base is a Kenwood TR-751A with a home brew 110W amp to a Mini Loop. The steerable beam is not in service any more and may not be put back.
UHF Freq is 440.700+ with PL 123.0. Cpverage is good in the foothills around Placerville. It has finally been linked to KJ6KO(441.450 pl 100) for better coverage in the Folsom/Sacramento area. This is new and there are still some minor bugs to work out but is fully operational.
The repeaters are open to all but the control codes for the remote are given to a select few and those who contribute to the upgrade of the system.
LEARN THE TONES!!!.......The remote is usually in a "monitor" state. That is the 2m remote is usually on 144.200 RX only. This means that you can talk over any SSB traffic you may hear. This mode is recognizeable by a single beep when the repeater is "kerchunked".
If you hear a "double beep" when kerchunked,....THE REMOTE IS IN THE XMIT MODE so you are being heard on 2m! This usually means someone is using it or forgot and left it on.
A "cuckoo" means the audio you are hearing is coming from the 2m side of the remote.
A "Backwards cukoo" or "BOOP BEEP" means the remote is shut off completely and is running as a standalone repeater.
This will be updated as the system is improved....