I happened across a discussion on building repeaters for Amateur radio, which lead to looking at GMRS repeaters (because apparently this is a potential source for inexpensive 70 cm Amateur repeaters), and that lead to seeing some discussion on illegal "parrot" repeaters for FRS. This made me think that maybe I might want to build a repeater. Not being committed to this in any way I be willing to spend kilobucks to this end but I could be convinced to spend a few hundred. Certainly if I can repurpose this investment for something else if I lose interest in a repeater.
For most every UHF and VHF Amateur radio band one can find a repeater for sale. These look to cost many kilobucks, far more than I'd want to spend on playing with a repeater. Even repurposing a GMRS repeater for this is not all that low cost, maybe lower cost than many other options but still more than a kilobuck. These repeaters often use special purpose radios, not really useful for anything other than a repeater. These are of course very popular because for the users it takes only a single band transceiver to use. The cost for the repeater is large to keep costs low for the users.
There's mobile transceivers out there that can do cross-band repeat. This sounds interesting because such a radio can be used as anyone might use any mobile transceiver, but can be put into use as a repeater with very little setup. After the need for a repeater has passed it can then returned to service as a mobile transceiver again. Using this as a cross band repeater for a large number of users (with "large" being more than two) means the users will need dual band transceivers, or two radios. This means low cost for the repeater but more expense for the users. What seems to be a popular radio for this is the Yaesu FT-8900, and with new radios selling for about $300 this is attractive.
This is where my seeing these illegal FRS and CB "parrot" repeaters come in. These are certainly illegal on FRS and CB but this should be legal on Amateur radio. That is unless I'm missing something. I did some searching on this and I will find people using parrot repeaters on Amateur radio but no description on how they were built.
For those unfamiliar with a parrot repeater they will wait for a signal on it's assigned frequency like any other repeater but instead of re-trasmitting it simultaneously on a different frequency they will record the audio. When the transmission ends, or the audio buffer is full, it will playback the received audio on the same frequency. These work for FRS and CB because the user radios do not need to be modified, and users do not need need two radios, to be useful. The drawback is this doesn't make for the most natural conversation because it means waiting for the "parrot" to repeat everything.
Has anyone built parrot repeater software for Amateur radio? The kind that would make use of a common personal computer and computer-radio interface? I'm thinking this might be useful for people that want to use an inexpensive single band mobile or base station radio as a repeater, and then the users of the repeater would only need an inexpensive single band radio as well.
Perhaps this just isn't considered all that useful since mobile transceivers capable of acting as a cross band repeater are not all that expensive, and dual band transceivers to make use of them aren't all that expensive either. If there isn't software for a parrot repeater then maybe there's software for turning a common PC, interfaced with a pair of suitable Amateur radios, into a repeater for people like myself that wants to keep a repeater "in a back pocket" in case a need to build one on short notice comes up.
