On 05/03/16 06:00, mike@midnighteng.com wrote:
RTL-SDR have no front-end rejection. While I like to use them for many things, They make terrible choice in repeater work.
No receiver has any front end rejection until you had a front end, which we'll do.
If your RPTR TX'r is in the same band, watch it totally de-sense that RTL-SDR.
No, as stated, these are remote receivers. There's no other noise generating equipment on site except the solar panel regulator.
What good would it be. Better off with a tyt/boafeng HT etc. And that's not giving those any credit.
Not a silly idea actually. A simple coax front end cavity, or notch to target the image might be in order.
You do need some scheme to vote/select the most valid one (to the core site) if it is different PL etc.
All built in to app_rpt isn't it?
FYI There are RTCM /voter systems for app_rpt if you want to do it right.
Too expensive when building a three repeater, six receiver distributed system. That's 24 RTCMs.
Since there is a left and right definable audio channel, I had always thought you could double-up on the dongles but never tried it.
My understanding is that cannot be done. Dongles are cheap as chips, so that's false economy. My original query as follows ;
For remote receivers, is there any work being done on using RTL SDR rtl_fm multiple-instances on one dongle, as multiple app_rpt IP connected receivers?
I ask, because it seems that a remote (RX only) site can host as many receivers as I can shoe-horn in the box, and as many as I can add solar-panels to feed.
It also seems, that I may as well host neighboring areas' remote receivers, and they host mine - for even larger coverage.
It just seems a stack of ten GM300s in there is the hard way, and it's a lot of current draw too.
There is a group of aviation-monitoring enthusiasts who have cracked the multi-channel thing, so it seems to be just a matter of feeding multiple MP3 streams to multiple app_rpt daemons. Anyone know how this works? S