DMR working two ways one day, now only receive

[kaluaone]

Set up my MD380 with code plug for Ohio. Starting talking on Sunday made numerous contacts on all Ohio. Yesterday tried to get on the net and all I could do was hear. Receive come in at all bars and heard everyone but when it was not receiving no bars showed. Light green to show repeater when someone was talking then when I key up the repeater doesn't hear me. Could be atmospheric? I live 40 miles from the repeater using a BTECH 20-40 watt amp with my MD380 on J pole. One day hitting repeater fine, next day cant hit the repeater.

Thoughts?

 

[KE5MC]

No personal experience, I’ve read that external amps and DMR may not play well together. Something about the amps switching time longer than the communication protocols allows. If amp has border line switching time it might be good one day and bad the next.

Google search should find more information on the subject.

Mike

 

[N2AL]

Here is a link for the BTECH amplifier. It lists the V25 & U25 (Analog) Amps, and the V25D & U25D (Digital) Amps.

http://www.miklor.com/COM/Review_DMR-Amps.php

Is it possible that your amp is an analog amp and not a digital amp? It’s a long shot but it’s worth a shot.

Another question, have you been able to transmit on the HT without an amp, and if so can any stations give you a signal report? If anything you can rule out the radio itself being the problem.

 

[kaluaone]

I bought the u25d which claims to be DMR compatible. I cannot hit the repeater from the radio itself repeater too far away..

 

[KE5MC]

Digital rating so that idea is out.

40 miles is a bit of a haul and atmospheric could play a part. J-pole in my opinion is not the best and a vertical with some gain would be to your advantage for the distance.

A couple of ideas to try out.

Is it possible to move your setup to higher ground or get more elevation for the antenna?

If possible monitor your power supply for voltage and current at the amplifier. If voltage drops I would say more than a volt suspect amp is not happy about that. If current is lower than typical then suspect PA failed.

Next level check is RF power out and SWR.

As a general check look at all the DC and RF connection for proper visual appearance.

Good Luck,
Mike

 

[kaluaone]

Mike,

Thanks, just bought a 30 foot tower. Looking to buy a high gain antenna. You have any suggestions.

Thanks

George

 

[KE5MC]

30 foot tower, sweet!

Which antenna is like asking about politics and religion. The link is to a Diamond antenna I had up for about 4 years before I moved. It was in very good conditions at that time. I used the UHF connector version as I don't get spun up about the difference between the two. I did use LMR-400 Ultraflex for 40 foot of feet line. It took a small beating by the woodpeckers and had a few holes in the jacket. The jacket for this cable is more rubberlike and seemed easy for the birds to have their way with it. While the jacket was holed it did not seem to effect the cable performance.

Once the feed line enters the house, use something more flexible to connect to the radio. RG58 or RG8x for a few feet will have minimal impact on the signal and save the connector on the HT.

Good Luck!
Mike

https://www.diamondantenna.net/x200a.html