Hello,
Firstly, apologies, this is a first post here so forgive me if this is in the wrong forum.
We have a BTR-800 on our show that is, for lack of a better word, freaking out. It seems to be two things that cause it to misbehave but we haven't managed yet to work out why either of these things affect the unit or how to fix it.
1) When the unit just has 2 transmit frequencies and 3 receive frequencies programmed it behaves flawlessly. However as soon as RX 4 (the 4th receiver) is programmed (or RX 5-10 that is allocated to the 4th receiver in the unit) it starts to think that the beltpacks are transmitting to RX 1 to 3 and are sporadically transmitting TA A&B. It doesn't lock on, it quite literally flicks between all 3 randomly causing pops on the output to the comms master.
Currently it seems to be stuck on TA A&B however in the past I have seen it cycle between Talk A / Talk B and also SA functions.
For problem-solving help on this, we have tried a Spare BTR with the same frequencies as the offending unit as it doesn't recreate the same problems. I have tried new frequencies on the offending unit and the same problem is present the moment a RX4 frequency is programmed. Additionally, it makes no difference whether a pack is switched on or not at the base. It has these issues without any beltpacks transmitting so this can be ruled out quickly. I've also tried completely seperating the unit from the comms master, receive antenna system and transmitting antenna system and the problem is still there. Mysterious no?
2) The same unit hates to be racked with other units. Currently it sits on a box next to the rack with our other BTRs using the same antenna system and will play nicely (assuming we haven't tuned RX 4). However, oddly, a similar problem as described above seems to occur once it is back in the rack with the other units. Isolating it seems to help but it's a bit impractical to say the least.
We have sent the unit back for repair to be told they couldn't find anything wrong with it, however that is clearly not the case.
Has anyone seen this problem before or has any ideas how to remedy? I've tried looking for a service manual for the unit just so I can at least try and see if I can find out electronically what could be happening, but I admit my electronics knowledge isn't that great.
Any thoughts are greatly welcomed!
Thank you
ETA: After an extra bit of exploration, the issues only seem to crop up when the BTR is tuned to user bank. I couldn't leave it long enough in a factory defined bank to see if the issue was still happening but it seems happy, but obviously we don't use a factory defined bank here...