Garmin TT15 gps dog collar

[ducati82]

Hi everyone.
I have a Garmin TT15 mini GPS collar with radio power problems. The handheld detects it up to a distance of about 50 meters and then loses it until it gets closer again.
I tried replacing the RF amplifier but the problem remained.
What could I check? I don't know much about RF.
If you need other information, just ask.

Thanks in advance

[harp]

Have you see this tread

https://www.badcaps.net/forum/troubl...ith-smd-please

Maybe some usefull information inside...

[ducati82]

Have you see this tread

https://www.badcaps.net/forum/troubl...ith-smd-please

Maybe some usefull information inside...

Hi harp, I had already seen that topic but unfortunately the problems are different and it didn't help me 😪

[CapLeaker]

I would check first how much RF this little thing is making. Maybe it's not the transmitter, could be that your receiver is deaf some reason or maybe there is something wrong with the antennas on either side. If An antenna has high SWR let’s say 3:1, then most of the power the rf amp makes gets reflected back to it and never makes it out the antenna.
I am not sure what distance this Garmin should be able to transmit, but I guarantee you it’s much more than 50m. More likely something like 5 - 10km depending on range line of sight and hills in between and antennas used.
For me it sounds like you got antenna issues somewhere.

[petehall347]

looks dubious

[sam_sam_sam]

looks dubious

What is the component that was in that soldering joint huh interesting picture
I would check every soldering joint for quality of the soldering joint when you see something like this

[ducati82]

I would check first how much RF this little thing is making. Maybe it's not the transmitter, could be that your receiver is deaf some reason or maybe there is something wrong with the antennas on either side. If An antenna has high SWR let’s say 3:1, then most of the power the rf amp makes gets reflected back to it and never makes it out the antenna.
I am not sure what distance this Garmin should be able to transmit, but I guarantee you it’s much more than 50m. More likely something like 5 - 10km depending on range line of sight and hills in between and antennas used.
For me it sounds like you got antenna issues somewhere.

I have another collar that works perfectly with that handheld (I tested it up to 5km)

[ducati82]

looks dubious

Is a photo problem, the soldering is perfect and in any case it concerns the GPS and not the RF circuit

[harp]

I have another collar that works perfectly with that handheld (I tested it up to 5km)

Are they the same model, maybe you can compare measurements one with other...

[petehall347]

Is a photo problem, the soldering is perfect and in any case it concerns the GPS and not the RF circuit

looks like it connects to gps to me

[CapLeaker]

I have another collar that works perfectly with that handheld (I tested it up to 5km)

Then something is either open or shorted to ground on the RF circuit. Here would be a RF probe handy…

[ducati82]

Are they the same model, maybe you can compare measurements one with other...

Yes, same model

[harp]

That is ok, but I also dont know much about RF, and interested in about learning basic rf troubleshooting principes.
What will I do while master come to help, is that replace antenas from working unit to faulty one and see if this change anything...

[CapLeaker]

I would replace that VHF antenna with a 1/4 wave wire antenna and bench test it from home for starters. To me it sounds like there is no VHF antenna hooked up.