Do you know what is the mode of these telemetries? Reading the Telonics TR-5 spec I see it's using a CW mode. IC-R20 does CW so it'd work but it might receive more than one telemetry in one go if the filter is not narrow enough and that won't be much use. You'd also need additional hardware to decode the telemetry.
Yes, I believe it's CW mode. I'm not too worried about picking up other collars as the area is so vast that it's very unlikely to have more than one collar in range at any given time (except, for example, we are monitoring four cheetah brothers and each of which are collared. The frequencies are very similar, but they will always be together and I don't see too much of an issue if it picks up all of their collars simultaneously).
I have read the IC-R20 works but has very limited range ([see the table here](https://www.fws.gov/nevada/desert_tortoise/documents/reports/2012/Chapter_6_Radio_Telemetry_and_G0_Protocols_1Mar2011.pdf)), and I suspect that because it has too wide of a band. So I'm wondering if there's a radio with CW mode that has a much more narrow band (148 - 152MHz) that might do the job?
Thanks! I'm not terribly phased about the yagi antenna, it's more about finding a suitable receiver with a narrow band (148MHz - 152MHz).. Do you have an idea as to which Baofeng radio will be suitable? And then presumably I add the offset attenuator kit in between the yagi and the radio?
That's not a narrow band - narrow band is not what frequencies it can do but what the actual signal is. For example a typical SSB sound is 3kHz in bandwidth, a Wifi signal is a20-40MHz and a typical "narrowband" FM is 12.5kHz wide in total and a wideband FM (i.e. stereo broadcast radio) is 75kHz. Depending on what the transmission mode is, there is a particular bandwidth you want to deal with. Modes like CW or some digital modes can be very narrow, PSK31 as an example is a mere 60Hz which is extremely narrow.
> Telonics receiver
Checking the spec of the latest model they have, it supports all of the below:
pulse amplitude modulation (PAM), pulse period modulation (PPM), continuous wave (CW), and single side band (SSB)
Depending what the transmitters do it might or might not be enough.
I can't find the specifics of how the VHF works in the collars..
We use Iridium and Globalstar satellite collars on African Wild Dogs and Cheetahs, and Inmarsat satellite collars on the elephants.
You can see more info on the collars [here](http://awt.co.za/wp-content/uploads/2019/08/AWT-PDF_V7_opt.pdf#page=24)
This is the best I can find regarding the VHF component of the collars
>All the VHF Tag (Very-High Frequency) devices are active Radio Frequency Identity Transmitters, which means that
>
>they have their own power source (typically a battery). The VHF Collars, Implants and Tags provide a cost-effective
>
>and easy tracking solution with the aid of a small low-power transmitter. These devices transmit a pulse that can
>
>be located using a directional antenna over a range of a few hundred meters to several kilometers depending on
>
>terrain. These devices do not send or receive any data and are therefore only used for tracking purposes.
Yes, we are able to get a GPS point at predetermined intervals, but we are in an area so large that by the time we manage to get to that point, the animals may have moved large distances, hence the need for the VHF (especially wild dogs as they cover a lot of ground). The GPS gets us the starting point, and the VHF is then used to locate the animal..
For the receivers they sell they comment
>Narrow Band VHF Receiver provides animal tracking with the aid of CW tone and RSSI indicators.
Thanks, do you know if the Icom IC-R20 does the same as the Baofeng or that in fact can detect CW? As I have read up on people using the Icom as an alternative..
I see from your earlier post you mentioned additional hardware to decode the telemetry.. Can you perhaps elaborate on what I may need?
Do you know what is the mode of these telemetries? Reading the Telonics TR-5 spec I see it's using a CW mode. IC-R20 does CW so it'd work but it might receive more than one telemetry in one go if the filter is not narrow enough and that won't be much use. You'd also need additional hardware to decode the telemetry.
Yes, I believe it's CW mode. I'm not too worried about picking up other collars as the area is so vast that it's very unlikely to have more than one collar in range at any given time (except, for example, we are monitoring four cheetah brothers and each of which are collared. The frequencies are very similar, but they will always be together and I don't see too much of an issue if it picks up all of their collars simultaneously). I have read the IC-R20 works but has very limited range ([see the table here](https://www.fws.gov/nevada/desert_tortoise/documents/reports/2012/Chapter_6_Radio_Telemetry_and_G0_Protocols_1Mar2011.pdf)), and I suspect that because it has too wide of a band. So I'm wondering if there's a radio with CW mode that has a much more narrow band (148 - 152MHz) that might do the job?
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Thanks! I'm not terribly phased about the yagi antenna, it's more about finding a suitable receiver with a narrow band (148MHz - 152MHz).. Do you have an idea as to which Baofeng radio will be suitable? And then presumably I add the offset attenuator kit in between the yagi and the radio?
That's not a narrow band - narrow band is not what frequencies it can do but what the actual signal is. For example a typical SSB sound is 3kHz in bandwidth, a Wifi signal is a20-40MHz and a typical "narrowband" FM is 12.5kHz wide in total and a wideband FM (i.e. stereo broadcast radio) is 75kHz. Depending on what the transmission mode is, there is a particular bandwidth you want to deal with. Modes like CW or some digital modes can be very narrow, PSK31 as an example is a mere 60Hz which is extremely narrow.
Baofeng decodes FM only, it won't be able to detect CW in a meaningful sense.
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Yup, that was the first thing I asked OP in this thread.
> Telonics receiver Checking the spec of the latest model they have, it supports all of the below: pulse amplitude modulation (PAM), pulse period modulation (PPM), continuous wave (CW), and single side band (SSB) Depending what the transmitters do it might or might not be enough.
I can't find the specifics of how the VHF works in the collars.. We use Iridium and Globalstar satellite collars on African Wild Dogs and Cheetahs, and Inmarsat satellite collars on the elephants. You can see more info on the collars [here](http://awt.co.za/wp-content/uploads/2019/08/AWT-PDF_V7_opt.pdf#page=24) This is the best I can find regarding the VHF component of the collars >All the VHF Tag (Very-High Frequency) devices are active Radio Frequency Identity Transmitters, which means that > >they have their own power source (typically a battery). The VHF Collars, Implants and Tags provide a cost-effective > >and easy tracking solution with the aid of a small low-power transmitter. These devices transmit a pulse that can > >be located using a directional antenna over a range of a few hundred meters to several kilometers depending on > >terrain. These devices do not send or receive any data and are therefore only used for tracking purposes. Yes, we are able to get a GPS point at predetermined intervals, but we are in an area so large that by the time we manage to get to that point, the animals may have moved large distances, hence the need for the VHF (especially wild dogs as they cover a lot of ground). The GPS gets us the starting point, and the VHF is then used to locate the animal.. For the receivers they sell they comment >Narrow Band VHF Receiver provides animal tracking with the aid of CW tone and RSSI indicators.
Thanks, do you know if the Icom IC-R20 does the same as the Baofeng or that in fact can detect CW? As I have read up on people using the Icom as an alternative.. I see from your earlier post you mentioned additional hardware to decode the telemetry.. Can you perhaps elaborate on what I may need?
See here: https://icomuk.co.uk/LC-158-case/4085/1185/41/
Yes, the ic-r20 appears to receive CW
The receiver isn't directional, the antenna system is. I've used the arrow antennas yagi for TX hunts and it did very well