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Posted
3 hours ago, gortex2 said:

The DB20G is a GMRS radio and not rated for anything in MURS, Marine, or HAM. Buy a certified radio to use in those bands. 

I have no plans to use it on anything else; I unlocked the frequency range because that also unlocks the number of memories that can be programmed for GMRS use. In factory trim, it only provides NINE additional GMRS channel slots beyond the preset 30 channels (out of 500 memory slots). Unlocked allowed me to load 29 repeater configs (granted, 16 of those are just the options on an RT97 mini-repeater) -- 20 more than the stock set-up.

But for something being sold as a 20W GMRS radio, why should two samples exhibit their WORST power output on GMRS frequencies (and by the same amount!), showing twice the power on the VHF band. Based upon the programmer (and the radio), it /is/ designed for operation in those other bands -- but has only been certified for GMRS in the US (cut-off of the image are entries for European PMR, though that may be a distinct firmware version as it reads "European version PMR", and Australian UHF CB)

image.png.c4433a64d1454d2f2f10c845e9e89e5f.png

I'll accept that there may be some component due to meter inaccuracy, but with the same configuration of meter&dummy load, the 15W Midland shows higher power on repeater frequencies, and almost the same power on simplex frequencies. If both radios are putting out their rated power (which is listed as 18W in the manual for the DB20-G), I'd expect to see the DB20-G showing 20% higher power than the MXT115 on any given channel (18/15 => 1.2) -- or ~15W.

 

Posted

I can't explain why your meter shows such discrepancies.

All I know is that others on this forum have measured this unit and received results that more accurately represent what it is capable of doing: 18 watts on UHF and 20 watts on VHF.

I have also conducted transmission experiments that show that this unit is capable of clearly hitting both simplex communications and repeaters that are many miles from my home base.

It even outperforms my Yeasu FT-857d on 2 meters and 70 cms.

I had two units: one in my shack and the other in my car and have been very happy with the results.

As I said earlier, you are unlucky to have received two defective units, especially since you only want to use it for GMRS.

When operating to full power specifications, the only two "complaints" I have about this unit is:

1) The CPS software is a bit cumbersome to work with, but there are workarounds; and

2) There is no 50 watt model.

AND for the price and size component, it can't be beat!

One guy on this Forum even installed one in his Ferrari! 

Posted
On 9/14/2022 at 5:22 AM, gortex2 said:

The DB20G is a GMRS radio and not rated for anything in ... HAM. Buy a certified radio to use in those bands. 

 

21 hours ago, MichaelLAX said:

Really?!?

Care to correct your misinformation?

 

5 hours ago, gortex2 said:

The DB20G is the GMRS version as stated on the sites. It specifically states is is a scanner on VHF and UHF. But forgot CA guy do what ever they want.

There is no such thing as a "certified radio" for HAM!

If someone opens up the DB-20G specifically to transmit on 2 meters and 70 cms; more power to them (about 18 watts on 70 cms and 20 watts on 2 meters ?)

And that's Mr. CA guy, to you!

Posted
On 9/14/2022 at 5:22 AM, gortex2 said:

The DB20G is a GMRS radio and not rated for anything in MURS, Marine, or HAM. Buy a certified radio to use in those bands. 

Wondering why the radio has the open option for other bands if it's not "rated" for them? What radios are specifically certified for ham (I might want one)?

Had my DB20(G) for about a year, unlocked it once I got my ham ticket and it's worked great since day one, on all bands/frequencies that it is programmed for...

oh yeah, another happy and satisfied CA guy here, enjoying experimenting in the hobby and staying radioactive!

Posted
6 hours ago, gortex2 said:

The DB20G is the GMRS version as stated on the sites. It specifically states is is a scanner on VHF and UHF. But forgot CA guy do what ever they want.

Responding to this...

 

53 minutes ago, WROA675 said:

Wondering why the radio has the open option for other bands if it's not "rated" for them? What radios are specifically certified for ham (I might want one)?

Using this as the trigger...

 

It is not certified by the FCC for operation on those bands -- at least, not under that particular model name. It is quite possible that the same circuit board is used in radios with different names, and sold for Part 90 Land Mobile Radio uses (though normally, those would be locked against front panel programming beyond maybe changing power and CTCSS tones). It is also sold in other countries (one of the "unlock" bands is Australian UHF CB 476-477MHz 5W -- GMRS only exists in the US [Canada's GMRS specification is closer to our FRS -- 2W power max, NO repeaters], another band is European PMR 446.0-446.2MHz [since it is listed as "version" the real PMR model may support digital voice capability] which falls into a US Amateur band).

Note that the unlock option is NOT documented in the manual -- and I've only seen two (maybe three) web-sites that reveal what is needed to access the other modes.

The FCC doesn't "certify" Amateur radios. As I recall, it merely "type accepts" radios sold for Amateur usage (which may include testing to ensure it does not operate outside the Amateur bands -- less a MARS/CAP modification -- and doesn't have excessive spurious emissions as sold; Amateurs are free to open the case and tweak stuff, add/change components, etc.) and assumes the licensed operator ensures the radio meets the "technical standards" of https://www.ecfr.gov/current/title-47/part-97/subpart-D (note that power amplifiers ARE certified -- basically to ensure that they can NOT be used on 11m CB). Amateurs are permitted to operate using scratch-built equipment without submitting it to FCC testing. In essence, any certified equipment, if it can be modified to operate on Amateur frequencies, if available to Amateurs. Note that FCC regulations for GMRS are such that supposedly anything that can be operated on Amateur frequencies is NOT going to be certified.

Quote

No GMRS transmitter will be certified for use in the GMRS if it is equipped with a frequency capability not listed in § 95.1763, unless such transmitter is also certified for use in another radio service for which the frequency is authorized and for which certification is also required. No GMRS transmitter will be certified for use in the GMRS if it is equipped with the capabilities to operate in services that do not require equipment certification, such as the Amateur Radio Service. All frequency determining circuitry (including crystals) and programming controls in each GMRS transmitter must be internal to the transmitter and must not be accessible from the exterior of the transmitter operating panel or from the exterior of the transmitter enclosure.

So... it is possible to obtain an LMR/GMRS (or marine/GMRS) dual certification -- as long as the LMR (part 90/marine part 80) aspect does not allow Amateur usage. The unlock sequence is NOT publicized by the maker, so -- as shipped, the firmware controls the "frequency determining circuitry..." to only allow transmission on GMRS channels. I suspect the testing lab was not informed of the "back door" unlock sequence.

 

Posted

 

1 hour ago, KAF6045 said:

Responding to this...

 

Good explanation and summary!

1 hour ago, KAF6045 said:

Note that the unlock option is NOT documented in the manual -- and I've only seen two (maybe three) web-sites that reveal what is needed to access the other modes.

It is, however, easily accessed in the official Radioddity software.

Screen Shot 2022-09-15 at 11.38.16 AM.png

NOTE: The settings in the screenshot above are from a default launch of version 2.02 of the Radioddity CPS software and are not representative of either my codeplug settings or the actual radio's default settings when shipped and received by the end user.

It offers the simplicity of a similar sized Midland radio, with all this extra versatility, at about a 40% discount in retail price, and other than @KAF6045's stated problem with its power output, I have not seen any other such complaints about this unit.

Still waiting for the 50 watt model! :)

Posted
On 9/14/2022 at 8:53 AM, KAF6045 said:

I'll accept that there may be some component due to meter inaccuracy, but with the same configuration of meter&dummy load, the 15W Midland shows higher power on repeater frequencies, and almost the same power on simplex frequencies. If both radios are putting out their rated power (which is listed as 18W in the manual for the DB20-G), I'd expect to see the DB20-G showing 20% higher power than the MXT115 on any given channel (18/15 => 1.2) -- or ~15W.

The defect in your power measurements, if there is one, is not necessarily linear, such that you can say that the defect should show a 120% increase in power in the DB-20G.

Posted
On 9/4/2021 at 5:20 PM, MichaelLAX said:

I love it!

i bought the Anytone AT-779UV, same radio! $99 at Amazon 

first mobile (because I hate HTs in a car) in 60 years of radio!

Instant mobile radio: mag-mount antenna and cup-holder mount and cigarette lighter plug!

Ask me any questions!

Michael,

What is the latest version of programming software for AnyTone AT-779UV? Is it 2.01?

Posted

I think you are correct but I use Radioddity v2.02 CPS software with my Anytone AT779UV. 

I have never updated the firmware. 

CORRECTED to list the v2.02 software the CPS software.

Posted
1 minute ago, MichaelLAX said:

I think you are correct but I use Radioddity v2.01 CPS software with my Anytone AT779UV. 

I have never updated the firmware. 

 

I'd have to double check version, but I've used radioddity's software with my 2 Anytones as well, and have not checked for firmware updates either.

 

Posted
1 hour ago, MichaelLAX said:

It is, however, easily accessed in the official Radioddity software.

I have other radios where the programming software supports other modes BUT it will fail to write that mode to the radio if the radio itself hadn't been first changed to the mode using mystic operations (for example, the Anytone 878UVII-Plus does not have the power-on button sequence supported by older 878 variants -- and I've not seen any confirmation that the third-party "breaker" software is compatible).

Hence, I did not try setting model information and then writing to the radio...

 

1 hour ago, MichaelLAX said:

It offers the simplicity of a similar sized Midland radio, with all this extra versatility, at about a 40% discount in retail price, and other than @KAF6045's stated problem with its power output, I have not seen any other such complaints about this unit.

Compared to the MXT115, I'd say it is "simpler" -- running the MXT115 menu system using two button on the front-panel, AND the up/down buttons of the microphone often ends up with the menu timing out before I can make a change. With most all functions on the DB20-G microphone it is much easier to change configuration.

I've encountered one reviewer on Amazon reporting low power though without details.

1 hour ago, MichaelLAX said:

The defect in your power measurements, if there is one, is not necessarily linear, such that you can say that the defect should show a 120% increase in power in the DB-20G.

None the less, it should be the same for any given frequency. In that situation, the 15W MXT115 display a half-watt more power on 467MHZ than the 18W DB20-G (with two samples of the DB20-G). Others have reported 20W range in VHF.

I never did see a response to my submittal on the Radioddity web site.

Posted
47 minutes ago, MichaelLAX said:

I think you are correct but I use Radioddity v2.01 CPS software with my Anytone AT779UV. 

I have never updated the firmware. 

Thanks.

That AnyTone AT-779UV 20W mobile radio for $99 on Amazon is very tempting.

Posted
10 minutes ago, MozartMan said:

Thanks.

That AnyTone AT-779UV 20W mobile radio for $99 on Amazon is very tempting.

Just bought one off of Amazon today.  I downloaded the AnyTone software and have everything setup for when it arrives.  I'll just have to do the button push trick and upload my file.  The only thing that seems off is the software and manual list the channel spacing or bandwidth as 25kHz but GMRS is supposed to be 20kHz (outside of the 467 frequencies).  Narrow band looks like 12.5kHz and matches what we're limited to on the 467 frequencies.

Posted
4 hours ago, KAF6045 said:

The FCC doesn't "certify" Amateur radios. As I recall, it merely "type accepts" radios sold for Amateur usage

 

The FCC doesn't "certify" *any* radios.  It does grant "type acceptance" for Part 90 and various subparts of Part 95.

There is no "certification" or "type acceptance" for Part 97 (aka ham radio).  Amateur radio is by definition an experimental service, and any radio can be used, even a home-brew one.  So if someone buys a DB-20G and "opens" it and uses it on 2m or 70cm, they are not breaking any FCC rules.

However, if they turn around and use that radio for GMRS or MURS, they *are* breaking an FCC rule, since the radio is no longer technically type accepted for Part 95e (GMRS) and was never accepted for Part 95j (MURS).

Posted

Channel spacing on GMRS is 25 kHz. 462.550, 462.575, 462.600 and so on. And indeed, channel spacing for low power and FRS-only channels is 12.5 kHz. Channel bandwidth is something entirely different, related to how much information could possibly be pushed through the specific channel. Term is not really applicable to what we are talking about. What chinese manufacturers can't properly translate is an occupied spectrum. For most of the radios I'm familiar with, it is 16 kHz for wide band, and 11 kHz for narrow band.

Posted
33 minutes ago, WRTJ886 said:

I’ll just have to do the button push trick and upload my file. 

Be sure to FIRST download and save the default Codeplug that comes pre-installed. 

Posted
11 minutes ago, wrci350 said:

However, if they turn around and use that radio for GMRS …, they *are* breaking an FCC rule, since the radio is no longer technically type accepted for Part 95e (GMRS)…

What if they first restore the factory settings and codeplug to then stop its abilty to transmit on the Ham bands, and then “turn around and use that radio for GMRS?”

Posted
13 minutes ago, MichaelLAX said:

What if they first restore the factory settings and codeplug to then stop its abilty to transmit on the Ham bands, and then “turn around and use that radio for GMRS?”

I know that's a rhetorical question, but if they "lock" the radio back to GMRS, then it is type-accepted again.  But you knew that already.

Posted
13 minutes ago, wrci350 said:

I know that's a rhetorical question, but if they "lock" the radio back to GMRS, then it is type-accepted again.  But you knew that already.

Another reason to: "Be sure to FIRST download and save the default Codeplug that comes pre-installed."

Posted
1 hour ago, WRTJ886 said:

Just bought one off of Amazon today.  I downloaded the AnyTone software and have everything setup for when it arrives.  I'll just have to do the button push trick and upload my file.  

Because the included software does not seem to allow for "cut and paste" from other software* (and as of the date of this post, there is still no CHIRP for this radio), be sure to "segment" your channels and leave empty channels in between each segment.

In that way as you grow with new channels to be inserted, there is existing space and you will not have to redo your codeplug from Channel 1 all over again

Empty channels are ignored when scanning or manually changing channels.

For example, my "segments" separated by empty channels are:

30 GMRS channels

GMRS Repeaters

5 MURS channels

PAPA channels (linked 2 meter and 70 cm HAM club in SoCal)

2 meter repeaters

2 meter simplex

440 repeaters

440 simplex

Local "scanner" frequencies of interest; and finally

494 - 500: Weather Channels

*NOTE: I believe you can cut and paste within this CPS software so that you can more easily create empty spaces between segments, since you have already written your first codeplug.

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