I think you mean the Chinese Rx's with the LED display. I've tested dozens of the mainland China 900MHz-1.3GHz systems with the hopes of finding a worthy model.
I'm no expert, but I'm wondering how much the fact that these units... especially the transmitter... have absolutely no heat sinking whatsoever may play into their continued operation over time?
I've posted my issue above
RE: incorrect frequencies on a system from China but when I took the TX apart to install in my own larger casing I saw that both the large voltage regulator on the back of the PC board as well as the output transistor up at the antenna connector were heat sink challenged, to say the least. Both got rather hot after only a few minutes powered up. Over time in such a tiny confined space they would probably burn out. Certainly the heat would become a factor in their proper operation and possibly could cause them to act up producing channel drift, switching on and off and/or reduced the TX output.
I'm looking to install hefty heat sinking to both components as I migrate to the larger casings. I'd be happy to post pictures of the mods if there is any interest
Anyway, like I said. I'm no expert.
Edited by scooterspal, 15 April 2011 - 11:52 AM.