BCD325P2/BCD996P2: Will BCD325P2 Detect DMR or NXDN when Using Close Call?
- Thread starter SatHunter
- Start date
I have not had any luck trying to pickup a handheld of either system type or P25 P2
You will do much better to capture the repeater out.
You will do much better to capture the repeater out.
Based on what has been posted in a number of threads, Close Call will not detect DMR.
Close call looks for two things- First, a signal that is significantly stronger than the background noise. (Offhand, I don't recall the exact figure, but somewhere in past posts was a note on how much stronger than the noise level a signal had to be to register in Close Call.)
Second, Close Call looks for a continuous transmission. DMR is not continuous, as it alternates between the two slots, which makes Close Call ignore signals from handheld radios. I haven't used Close Call for DMR, for that reason, but it might be that a stronger signal, such as from a repeater might catch Close Call's attention.
Since the fur smaller cities in my county, that were using NXDN, have switched to a regional P25 Phase II system, there is very little NXDN close enough to me to try Close Close Call. Perhaps someone else can clarify whether or not it recognizes NXDN hits.
Close Call works just fine on DMR, but only on a repeater output. It will not capture a handheld/mobile. And it works for NXDN, either repeater output or mobile side.
Thank you very much for your reply! I’m 2 blocks away from the repeater so I’m sure the signal will be very strong. Also do you know if DMR/NXDN will be detected when doing a search?
Yes.
BC_Scan
Member
I was able to capture 16 channels of rptr + simplex with close call on a 7550 I bought on line, my 436 captures DMR /NXDN simplex everywhere I go if its in close call mode, however for the life of me I cant get my local Costco that changed from vhf to uhf DMR in close call , so it seems to be a hit or miss thing
NXDN isn't an issue. DMR simplex/input has always been miss for me and everyone else here as far as I know. Odd that it works for you.
Why, when a DMR signal is transmitted by a repeater can it be heard on Close Call capture but not on the originating base, mobile or handheld?
The repeater does one thing, increase the range of a base, mobile or handheld. We all know that’s because it’s re-transmitting the received signal at a higher wattage and (usually) from a higher vantage point. But it’s the same signal that passes thru the repeater from that handheld, mobile or base, just stronger.
So, if you were close enough to that mobile, base or handheld, where the signal is strong, why wouldn’t Close Call capture it?
I tried it with my DMR ham mobile and my SDS200, both mounted in my truck and did not capture it using Close Call, which bears out what you have said. My first assumption is that the DMR radio is overloading my scanner-there’s only a matter of 12-15 inches between both antennas. While this spacing might have a bad effect on the scanner’s ability to hear, it may well be what you speak of instead. (And before someone gives me hell for placing a transmitting antenna too close to my scanner antenna, something I am aware of, previous installations worked just fine so I never even gave it a thought when I installed my gear in my 2021 pickup with a BackRack, which I use as my antenna farm… 3 antennas.)
The repeater does one thing, increase the range of a base, mobile or handheld. We all know that’s because it’s re-transmitting the received signal at a higher wattage and (usually) from a higher vantage point. But it’s the same signal that passes thru the repeater from that handheld, mobile or base, just stronger.
So, if you were close enough to that mobile, base or handheld, where the signal is strong, why wouldn’t Close Call capture it?
I tried it with my DMR ham mobile and my SDS200, both mounted in my truck and did not capture it using Close Call, which bears out what you have said. My first assumption is that the DMR radio is overloading my scanner-there’s only a matter of 12-15 inches between both antennas. While this spacing might have a bad effect on the scanner’s ability to hear, it may well be what you speak of instead. (And before someone gives me hell for placing a transmitting antenna too close to my scanner antenna, something I am aware of, previous installations worked just fine so I never even gave it a thought when I installed my gear in my 2021 pickup with a BackRack, which I use as my antenna farm… 3 antennas.)
Because the repeater transmits on both timeslots all the times, so no discontinuous transmit. The handheld only transmits on 1 timeslot, so it only transmits for 30 milliseconds at a time, which is too quick for Close Call to capture.
- Joined
- Jun 30, 2020
- Messages
- 2,019
The answer is "it depends". It will trigger on any non-TDMA signals. Others have described those above.
DMR Repeaters, for example, transmit both slots full time, so that is technically not a "TDMA" signal - it is constant carrier.
I am considering getting the DMR & NXDN upgrades for my radio with all of the positive feedback on how the 325 handles them. I have a couple of questions: can the 325 separate DMR slot 1 and slot 2 so that voice communications don’t ride over top of one another? And is there a way to get the upgrades in Canada? With the exchange on the dollar a $60 DMR upgrade turns in to $85. Same deal for the NXDN upgrade. Almost $200 in total
If you program the scanner correctly, yes it will distinguish between slot 1 and 2.
Getting the codes from Uniden is the best way.
I spread it out over time. I got NXDN first, next month DMR, and much later when it came out the waterfall for the SDS100.
Getting the codes from Uniden is the best way.
I spread it out over time. I got NXDN first, next month DMR, and much later when it came out the waterfall for the SDS100.
