can you lower the power output when its repeating? if your just relaying to your driveway for a repeater you could otherwise reach w/a HT, you could probably run it at low power.
Fairly sure in both cases I was TX on low (5watts) on the 70cm side. The 2m TX was on 35 watts, but the only TX was my check in to the net.@ultraclyde, what power level were you running? The manual for my FT-8800 states that only low (5W) can handle cross band repeat. That's something people forget when they see that feature, these radios are not designed for repeater use and cannot tolerate much TX power at 100% duty cycle. Which is what you're asking it to do, it's constantly transmitting on one band or the other.
Are you in the rag chew or just listening? If you're only monitoring the radio may have a pretty high duty cycle but it still gets some breaks when the repeater unkeys. If you jump in and talk when the repeater drops the radio is never not transmitting and never having a break is where the manufacturers are concerned. Junction temperature rise isn't linear with duty cycle and the failure rate between running semiconductors at 100% compared to even 75% or 80% is statistically very significant.What radio were you using? I've used an Icom IC-2340, IC-2350, and IC-2720 for years in cross band operation. Sometimes they end up transmitting on low power for hours at a time when some of the old retired guys get to rag chewing on the repeater I'm monitoring.
3 minute timer is for continuous transmission...and is very common even for big repeaters. It is also a nice failsafe in case your HT gets 'stuck' on in a backpack or whatever (it happened to me once). It is really not that big of an issue.What radio were you using? I've used an Icom IC-2340, IC-2350, and IC-2720 for years in cross band operation. Sometimes they end up transmitting on low power for hours at a time when some of the old retired guys get to rag chewing on the repeater I'm monitoring. I've never had any problems out of them in probably 24 years.
When looking for a new radio I once considered a Kenwood TM-V71A until I learned it has a 3 minute time out timer in cross band mode. This would be unacceptable for my use. It also makes me wonder if Kenwood is worried about their finals.