GB3LI – RB10
433.2500 MHz, FM Analogue Repeater
|LAT/LONG||53.460946 / -3.013586|
GB3LI FULLY FUNCTIONAL.
As you know I have had no time to work on a replacement repeater so had to try and keep the old one going. Fortunately Jeremy G4NOY who has been helping me to keep the old one ticking over volunteered to produce a new repeater. We also have to thank the following:- Andy GW1SYG, for hardware and time spent on initial alignment/configuration of the repeater, Dave G4PGO, Richard G8NDD, and I supplied additional hardware and Jeremy completed the final assembly, configuration and testing.
We now have a Tait T800 slimline series base station and Zetron logic complete with 82.5hz CTCSS!!!!!! [1750hz toneburst access is no longer supported].
When we did a final power output check on the old equipment before removal we found it was down to 10W so the 25W of the new one gives a noticeable improvement in signal strength.
The new repeater was installed on Wednesday 3rd of June and the 28 year old one taken to bits. We are very lucky soya dust is non conductive as It was completely covered in the stuff. Original paperwork on the repeater reminded us that the first one was installed 1975/6 with the one we have just taken out installed around about 1987..
Ken G3WIC, keeper GB3LI
Our thanks to Ken G3WIC, Andy GW1SYG, Dave G4PGO and Richard G8NDD, along with Jeremy. for your hard work..
For the last week or so GB3LI RX has been getting blocked by its own TX. I think its a poor connection in one of the cavities in the RX path as you get the same effect when adjusting them. (a bit like a noisy volume control until it makes a good contact).
Today (Wednesday 7th November) when I checked GB3LI it seemed to clear itself for a very short time, then the fault returned.
G4NOY and I are planning a site visit on Friday 23rd November if the problem is still there.
I will keep you all informed.
Ken G3WIC, keeper GB3LI
SITE VISIT on 30th August 2012
Jem G4NOY and myself went to the GB3LI site as the repeater was in continuous TX mode with no talk through. We found there was no power on the RX. Unplugging the power cable, removing the RX from the cabinet and plugging up restored power to the RX. (Can only assume it was the tarnished contacts).
We then had a another look at the low sensitivity RX problem. No faults found, the bias on the front end RF stage FET’s was within spec etc. . We decided to once again retrim all RX stages and try and get the oscillator injection to the FET mixer as high as possible. (we also fitted a new preamp, but the RX if anything was better with the original preamp so we put things back as they were.)
After trimming everything that we could (more than once) the gain (sensitivity) increased by about 6dB. On site RF measurements show that the RX is now back to its original sensitivity. Reports from distant stations supports this