Is my Radioddity DB20-G outputting any power?

[redshirtsteve]

Hello, I just received and set up my DB20-G with a power supply, and a DPDProductions GMRS Blade antenna and power supply, but I think I am running into a problem when I transmit, and that is, the power meter does not light up the way I expect it to.

 

 

Edited April 20, 2022 by redshirtsteve
Added image

[wayoverthere]

25 minutes ago, redshirtsteve said:

Hello, I just received and set up my DB20-G with a power supply, and a DPDProductions GMRS Blade antenna and power supply, but I think I am running into a problem when I transmit, and that is, the power meter does not light up the way I expect it to.

 

 

I'll try to peek at what the meter looks like on my anytone with low power tx sometime today, and if the tx disable is in the menu.

Three things come to mind to check: swr (to rule out a cable issue causing it to cut power), whether tx is disabled on that channel in the programming, and (the big one that stands out) if plugging in something else to that 12v socket displays as a draw on the meter....heater, 12v fridge, whatever. I'd expect to see some current draw on key up.

[WROZ250]

1 hour ago, redshirtsteve said:

Hello, I just received and set up my DB20-G with a power supply, and a DPDProductions GMRS Blade antenna and power supply, but I think I am running into a problem when I transmit, and that is, the power meter does not light up the way I expect it to.

 

 

Your display suggests you are transmitting on low power.  However, even on RX your power supply should be indicating some current draw which it appears not to be doing.  Low power TX draws slightly more than RX.  Also, never troubleshoot power with the system antenna, use a dummy load.  But something is definitely wrong in this photo.

[redshirtsteve]

Thanks gang, I am now reaching out to Radioddity, and hoping for the best.

I did test the power supply with another device, and I did see what seemed to be an appropriate power draw, so I think the ps is in good order.

TX Lock does not seem to be enabled, and in fact, it seems hidden in the programming app, and the menu system on the radio (though it is mentioned in the manual?)

Your input is much appreciated!

[wayoverthere]

Took a quick look at mine in the truck (currently unlocked to full dual band to toss in the better half's car for a recent trip), and the one bar on the on screen meter and red tx light are consistent with low power transmit on mine.

I found "tx inhibit" in the menu, though it may only be there in unlocked mode. In the software, you have to hit the >> at the end of the row to go into channel details, and it's toward the upper left, iirc.

I want to say when I checked on my psu, it showed around 3.5a draw on high, but I can pull it inside and check low power.

from here, dummy load or not, I'd want to get it on a meter and check power output directly..just give your call sign and say something about testing when you key up, if you don't have a dummy load....won't be a 100% accurate figure, but close enough to see if the output is there or not, and what the swr looks like.

Touching base with Radioddity isn't a bad idea as well.

[SteveShannon]

Show us how you have it wired to the power supply, please.  I don't know whether the meters on the front reflect the power delivered to the rear outputs only or the rear outputs plus the two outputs on the front (cigarette lighter + one more connection which is limited.)

 

[donniefitz2]

Is it unlocked in UHF/VHF mode? What frequency is channel 3 programmed to (assuming it's not default GMRS)? Is the radio actually transmitting?

[WROZ250]

2 hours ago, donniefitz2 said:

Is it unlocked in UHF/VHF mode? What frequency is channel 3 programmed to (assuming it's not default GMRS)? Is the radio actually transmitting?

By Default, CH3 is 462.6125 (simplex) and on a GMRS radio, the power limit is 5W.

If the DG-20G was unlocked from GMRS to VHF/UHF, the new default CH3 would be blank.  Which in theory, would take it out of the channel rotation (never shows up when you hit the up/down buttons.

 

[donniefitz2]

Yep, that's why I was asking. Hard to say what's going on without knowing the state of the radio. 

[wayoverthere]

Back with a little further test data to share. I grabbed the other one out of the beater, since that one isn't attached (just shoved in the slot in the console) and I was in that car today.  Both are programmed near-identically, really differing only in which channels show up in the scan (the one in the car is doing ham/GMRS dual duty, one in the truck is primarily for GMRS with a Icom for ham). 

Even unlocked, I did my best to stick as closely as possible to the part 95 configuration (save that 'able to access other services' thing).  For the GMRS channels, 1-7 are set for low power, 8-14 are rx only.

Hooked it up to my PSU (alinco dm30tr), hooked up the sw102 and dummy load, and keyed low power on ch 3 (462.6125).  PSU shows 1.6a draw, 13.9v (radio shows 13.8v). The Surecom showed the expected 1.0 swr for a dummy load, and 5.12 watts out. Tried it again with an antenna in place of the dummy load (midland mag mount on a piece of sheet metal, 5/8 wave base loaded whip) also shows 1.0 swr, with 4.48 watts.

Still curious for a meter reading on output, but like @donniefitz2 I'd like to know what's up with the programming in the radio, and could it be "CH 3" is something outside of GMRS and in lockdown mode it's just not actually transmitting?  Given the number of issues we've seen with some of the brands with all kinds of funky things showing up as default programming both post reset and out of the box (and the fact that, despite being sold as part 95 gmrs-locked radios, both of mine came unlocked), verifying the programming is probably a good next step (outside of solutions Radioddity may offer).

[MichaelLAX]

As I recall, the original batch of DB-20G's that were released by Radioditty were "locked down" to Low "L" power on Channels 1-7 as well.

Do this to check out the Firmware Version number:

Power Off

Hold down V/M button

Power On

The Screen should say:

Mode:

GMRS

(blank line)

V2.xy

What version of Firmware does yours show and is it GMRS or opened up to transmit on other frequencies?

I still successfully use V2.26 and 2.27 and I am aware of Radioddity offering firmware updates to 2.30 (although I am not sure what this version adds).

Also what version of Radioditty programing software are you using?

Version 2 of the programming software (version 2.01 or 2.02) came with the Firmware Upgrade that allows for 5 watts on Channels 1-7 and 20 watts on Channels 15-22 and the Repeater Channels 23-30.

From the Help Menu: