Help With Repeater

[speedway_navigator]

All good advice. Also consider the short jumper cable between the repeater receiver and the duplexer should be a double-shielded silver-plated cable with silver plated connectors. This cable is the most important when using a duplexer, as it reduces the likelihood of any RF from your transmitter leaking into the receiver and causing desense. Some quality RG cable types for jumpers are 214 ,142, 223, 400.

I had a piece of RG142 on a duplexer cause intermod at a Bearcom event. When I setup my duplexer with 4 repeaters on a combiner it tested fine on the Bearcom channel but a few minutes later 2 different users were on at the same time and it sounded like crap. I wiggled each one as I was TXing and found it.

This was before VNA days and I didn't bother to test the cables because 'they worked fine in the shop' before they shipped.
I tell techs who service mobile repeater trailers to watch for vibration damage, we tend to make too may assumptions it will work this time because it did last time.

 

[prcguy]

I had a piece of RG142 on a duplexer cause intermod at a Bearcom event. When I setup my duplexer with 4 repeaters on a combiner it tested fine on the Bearcom channel but a few minutes later 2 different users were on at the same time and it sounded like crap. I wiggled each one as I was TXing and found it.

This was before VNA days and I didn't bother to test the cables because 'they worked fine in the shop' before they shipped.
I tell techs who service mobile repeater trailers to watch for vibration damage, we tend to make too may assumptions it will work this time because it did last time.

The key point here is Bearcom, who is to say the combiner was tuned properly or even had isolators.