QYT D68 - 32 channel UHF DMR handie

[bigbloke]

Ive received a couple of sample QYT-D68 radios - 32 channel analogue / DMR sets 400-480 MHz

see : https://www.youtube.com/watch?v=9L3M304_jiM

Very Solid, with good audio (for DMR)

Software and programming lead actually works (which is a plus for an early release chinese radio) although
the software does bug out occasionally under Xp without warning

I've not had them in the lab yet , thats for next week , but I have the perception theyre just a tiny bit
on the deaf side . The lab will tell.

Supports DMR with Basic Privacy, Analogue with CTCSS /DCS , no scrambler , quoted at 4w out . voice announcement of
selected channel (16 channels per zone and two zones(

Uses kenwood compatible speaker mic pinout.

Regards

BB

[BK]

Looks solid in the video. Do you know what vocoder it uses, I'm guessing it'll be a chinese one, so not compatible with Motorola DMR kit?

What exactly is 'Basic Privacy'? I'm only familiar with the ETSI standard AES encryption and Motorola's proprietary Basic and Enhanced Privacy, I'm guessing it's not the Motorola flavour?

Edit: looking at the 409shop website I notice Puxing have a digital radio too, the PX-680D, hadn't seen that before.

[bigbloke]

Looks solid in the video.

I would describe it as motorola GP300 soliditity in a radio half the size

Do you know what vocoder it uses, I'm guessing it'll be a chinese one, so not compatible with Motorola DMR kit?

AMBE2 - fully compatible with DMR - its a DMR / analogue radio

What exactly is 'Basic Privacy'? I'm only familiar with the ETSI standard AES encryption and Motorola's proprietary Basic and Enhanced Privacy, I'm guessing it's not the Motorola flavour?

it is , I believe compatible with motos basic - basically 16 user definable / selctable two hex byte keys that can be assigned to any channel

certainly interoperable with CS700 / MD360

Edit: looking at the 409shop website I notice Puxing have a digital radio too, the PX-680D, hadn't seen that before.

whole raft of them coming out now !

regards

BB

[BK]

That's impressive. Does it have a scan function?

[bigbloke]

yes ,

each programmed channel can belong to a scan list - you build scan lists in the software . e.g

list 1 = mem channel 1+2+3
list 2 = mem channel 4+5+6
list 3 = mem channel 1 to 16

assign list 1 to chan 1 , select chan 1 and scan , you scan 1-2-3-1-2-3
assign list 2 to chan 4 , select chan 4 and scan , you scan 4-5-6-4-5-6
assign list 3 to chan 16 , select chan 16 and scan, you scan all 16 chans

you can also configure a channel to start scanning as soon as its selected (tick box in software)

regards

BB

[bigbloke]

set up a simple parrot test rig this morning . i may well be doing these sets a disservice on digital sensitivity
even if my initial impression of the analogue side wasn't favourable

one slightly annoying factor was that when economiser (Battery save) circuit was switched in It spikes the earphone socket enough to trigger the parrot unit . I couldnt hear it with an earphone (bit old and deaf) but as soon as I turned
off battery save it worked fine. I'll plumb the rig into an audio analyser next week and see whether its LF rumble or a high pitch whine thats the root cause.

although there were spots where i expected service and got none , there were far more places where i didn't expect analogue to get , yet digital did!

Of particular note was one location where over 400ft of sandstone hill obscured a 2.5 mile path yet I still had comms.
that was handheld indoors (upstairs) to handheld inside a VW transporter.

more observations as they happen, but based upon current digital performance I can see these as a replacement for my trusted analogue LT3260s

Regards

BB

[BK]

certainly interoperable with CS700 / MD360

Do you have these radios? If so, I'd be interested to know what you think of them.

[bigbloke]

er... think i said that in the first line of my first post BK?

Ive received a couple of sample QYT-D68 radios - 32 channel analogue / DMR sets 400-480 MHz

so yes - i have a pair to evaluate

or were you referring to the cs700 / md360 ? ( sorry! been a long day!) in which case i have a cs-700 yes


regards

BB

[BK]

or were you referring to the cs700 / md360 ?

Yes, that's why I quoted the bit about the cs700 / md360
I just thought a comparison would be interesting.

[bigbloke]

A quick interim post .

Set up the D68 and the CS-700 in the lab at lunchtime. Sadly there was no dmr capable analyser on site so had to test in "old mode" :-)

with open squelch I tested the sensitivity of both radios.

Cs-700 -123 dBm for 12 SINAD
D-68. -121 dBm for 12 SINAD

BUT !

my perception of the D68s deafness was down to squelch sensitivity!

The CS700 squelch would stay open at -120dBm and would 'sputter' down to -122, below which it would close.

The D68 however required -117 to open the squelch [50% more signal] and hence the initial impression of deafness.

In fairness , this could be down to my settings in firmware , but as i cant check this (cable in wales) i'll reserve judgement until after validation

Regards

BB

[bigbloke]

I have been publically skeptical about digital radio sensitivity. In my day GSM system floor was around -108dBm whereas analogue could be got down to -126dbm in a handheld and lower still in base/mobiles. I laughed out loud on a D68 advert that quoted -117 for 12 analogue and -177 for digital and simply assumed it was a typo....

however...

Yesterday on simplex DMR, with a 5w UHF handheld / helical in house on a parrot tester to a second handheld in the van I have repeatedly heard my own "echo" over a 9 mile, Non line of sight path obstructed by not one, not two but THREE significant hills (east newport to risca/ cwmcarn border for those who know the topology)

Suffice to say ..... I'm not laughing anymore! Im fair gobsmacked !

still dont believe -177!...but !

Regards , the chastened..

BB

[radiosification]

Yesterday on simplex DMR, with a 5w UHF handheld / helical in house on a parrot tester to a second handheld in the van I have repeatedly heard my own "echo" over a 9 mile, Non line of sight path obstructed by not one, not two but THREE significant hills (east newport to risca/ cwmcarn border for those who know the topology)

You have a DMR parrot repeater? I was thinking of experimenting with this and would love some more info on how yours is set up.

[bigbloke]

I have a parrot unit that I occasionally use for testing - its not left on , and the radios I've been using it with has encryption
so to find it people would need my frequency, colour code, slot , talkgroup ID and 4 hex byte encryption key.

It simply plugs into the mic and speaker port as they are both kenwood compatible and only ever gets run on a handheld antenna
during "one man evaluations" . With DMR you need to keep the radio and antenna at least 1m apart to stop the Pulsed RF getting into
the audio capture.

the unit is a CRP-101:

http://www.cybercom.com.tw/crp-101.htm

you need a different set of leads for each radio type though e.g. the CS-700 wont work with Kenwood leads.

You set the radio volume to about 80% and the unit volume to full tilt and thats it - talk to yourself :-)

Regards

BB

[radiosification]

I have a parrot unit that I occasionally use for testing - its not left on , and the radios I've been using it with has encryption
so to find it people would need my frequency, colour code, slot , talkgroup ID and 4 hex byte encryption key.

It simply plugs into the mic and speaker port as they are both kenwood compatible and only ever gets run on a handheld antenna
during "one man evaluations" . With DMR you need to keep the radio and antenna at least 1m apart to stop the Pulsed RF getting into
the audio capture.

the unit is a CRP-101:

http://www.cybercom.com.tw/crp-101.htm

you need a different set of leads for each radio type though e.g. the CS-700 wont work with Kenwood leads.

You set the radio volume to about 80% and the unit volume to full tilt and thats it - talk to yourself :-)

Regards

BB

Why do you have to keep the radio at least 1m away from the repeater? Surely when the simplex repeater starts recording, the receiving radio will not be receiving and therefore not creating pulses that will appear in the audio? Or is it from the wire when the repeater is playing back the audio and the radio is transmitting?

I previously assumed that you meant with Motorola DMR equipment. I wanted to try it with my MotoTRBO radio, but I don't know if it's possible or not. I don't know if they would still key up if I was using an additional adapter for the multi pin connector thing on MotoTRBO radios.

Also I think it would be possible to just listen for the colour code, and TG. Slot is not used on simplex DMR so anyone could use either slot and still get in (unless you are using DCDM (see here: http://cwh050.blogspot.co.uk/2012/12/dcdm.html) )
Most decoding programs now can get the colour code and group code pretty easily. The encryption would still prevent people from using the repeater as a repeater, but if others transmit in the clear to it, you would still hear it back out encrypted.

[BK]

if others transmit in the clear to it, you would still hear it back out encrypted.

Unless the QYT D68 works differently from Motorola Radios? Apart from backwards compatibility while you're transitioning to digital, it would actually make more sense if the radio only received what it was set up to transmit, i.e. if you're transmitting encrypted digital you don't actually want to receive analogue or unencrypted digital.