Got a pair of Retevis P1's.

[QRZ-934]

Arrived after a couple of weeks, these are a radio that has no display, built it appears primarily for business users but covering 136-174 and 400-480 mhz.

Output powers quoted at 0.5 -5 and 10 watts.
Theres a video on YT showing them in operation and the max power figures quoted hold up.
256 channels programmed via their own cable (c9260A) is what theyve sent, unfortunately my aging pc refuses to read them, apparently its because of the OS version Im using, to be addressed shortly.
It does DMR and analogue and is compatible with motrbo motorola radios.
Interesting aspect of them is they can act as a repeater, its not something ive tried with them as youd need 3 of them to accomplish the task, but again YT shows the method.
By far and away for me at least is the alluring fact that these have aes256 voice encryption, also aes128 and ARC4 which for those who dont want snoopers listening in makes for a useful and in the case of aes256 an uncrackable at this time security benefit.

YT radio test shows clear audio on RX and TX on analogue, however the video doesnt go into the digital aspects of the radio so only long term tests will demonstrate its real world abilities, certainly the two RT3's ive been using have proven their worth on DMR with 30 mile contacts in total clarity, encryption enabled or not.
These would make great point to point radios with a suitable beam antenna and minimal power with little chance of being overheard.

Testing the stubby antenna thats supplied on 400 mhz gave 1.76:1 swr on the mini1300.
420 mhz gave 1.3:1 sweet spot is around here.
At 480 mhz swr is 4.3:1 so useless that high up.
At the 440 mhz midpoint its sitting at 2.1:1.

At 136 its over 1999:1 so not viable, same at 174 as expected.
User software is similar to the RT3 radios so will see how that works out when ive gotten into it, then for some tests in the real world.

[scanhermit]

I see on the Retevis website that the antenna is removable. You could fit antennas that more closely match your desired frequency.

[QRZ-934]

Yes Ive seen those, seems to be the eternal problem that many just dont seem to be matched and need modifying to achieve better swr.
Still will see how theses go and can use my modified N771 on the baofeng as thats worked out great.

[scanhermit]

I have no antenna tester so I've no idea what the Retevis RHD-771 antenna SWRs like on the PMR446 band, on my RT24 handsets but since contacts tell me that my signal is greatly improved by it, I don't suppose it's too high.

[paulears]

Im a little confused? I was under the impression these radios were UHF only? Thats why i did not buy any recently?

VSWR is almost impossible to measure on the shorter antennas, and hopelessly inaccurate on stubbys. You cannot measure what the radio sees. Removing the antenna to measure in with a cable and meter destroys the match. The combination of the radio, the hand holding it and the antennas distorted radiation pattern caused by the helical matching. Removing the antenna and measuring somewhere else gives readings that might be better or worse than when on the radio! Stubby antennas are always a compromise antenna, but in situations where signal strength is not critical, but size is, then having a terrible antenna doesnt matter. The radios are designed to cope with high VSWR and dont care about a perfect match. They drop the output power down, but that doesn't really matter that much. In the UK in the 80s/90s the most popular police UHF radio had a tiny stubby antenna. Service area was fine. Output power was less than a Watt!


Measuring VSWR anywhere other than on the radio makes little sense, and physically, you cannot even do that, so any test results cannot be verified at all. All those mega antennas advertised can be put on a sheet of metal, and fed through a hole, and measured. Many get praised, many get the opposite. On the radio, the bad ones often do well, because they're just longer than the original!

These of course are NOT licence free, remember.

[QRZ-934]

So the programming issue was resolved and the digital channels coded in.
After travelling some 40 miles distant a family member tested the radio at the other end with the results being absolutely crystal clear audio.
No distortion or dropping out, it was clearer than my mobile phone.
Probably the next range test(still on the stock antennas) will be conducted at 80 miles and see how that holds up.

Yes Im aware that theyre not licence free, but not something thats ever going to be an issue judging by ofcoms lack of any enforcement action since 1998!
Yes it appears youre right regarding the frequencies, you can get them in both vhf and uhf but it seems not as a dual bander, not really a deal breaker for me and after checking the inside of the battery cover the label indeed confirms 400 to 480 uhf even though the manual states otherwise.
Thanks for the antenna measuring advice paul, appreciated.

[paulears]

You got 40 miles? My home is just over half a mile from the office. Hand held to handheld none of the radios i sell can make it. Not even ones with close to ten Watts. Is your 40 miles mountain top to mountain top? I have never in my career had handhelds with this kind of range. You must be in some kind of magic kingdom for 40 miles to be achievable. Wow!