Flex Paging, rtlsdr, rtl_fm, multimon-ng settings. ? ? ?

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Flexme
Posts: 10
Joined: Wed Jan 30, 2019 1:00 am

Flex Paging, rtlsdr, rtl_fm, multimon-ng settings. ? ? ?

Post by Flexme » Wed Jan 30, 2019 1:28 am

NOTE: To get this out of the way and before any one suggests it....

I am aware of the applicable laws in my area in regards to pager reception (decoding) and whom is authorized to do so. I am AUTHORIZED for the reception of this data under the applicable laws of 47 CFR 2512 et seq. Not here to have discussion on the law, just tech discussion.Thanks.

So with the above out of the way...

I am trying to get Flex reception to work as reliable as my POCSAG verifier does.

I've played with the settings on rtl_fm all over the gambit of options to no avail, the best I get is just lots and lots of garbage...

I've tried rtl-SDR V3 dongles.. generic dongles wirth FIC012 tuners, with 820T tuners... .

No joy, just garbage....

The SAME dongles are ALL used with OP25, sdrtrunk to receive P25 PI and PII systems, as well as POCSAG1200 on a VHF channel.. all work 100%. My POCSAG verifier runs 24/7/365, with probably a good 99.9% accuracy...but as we batch up things the redundancy in the signal makes up for the occasional garbled decode.

But Flex. vexes me....

ppm IS set based on what works for POCSAG, P25 and even just regular NBFM...

Hardware runs the gambit of a couple of dual core PC's to Pi3B+....

I use:

usr/local/bin/rtl_fm -d 1 -p 70 -g 49.6 -o 4 -A lut -s 22050 -M fm -f

for the the POCSAG verifier, it runs on a generic dongle... thus the -p 70, but similar -p settings for others and they work just as well..

Piping that to multimon-ng for Flex just yields basically this:

Code: Select all

LEX: Phase F Fixed 1 errors @ 0x01000000 (0x177e773f -> 0x167e773f)
FLEX: FrameInfoWord: cycleno=03 frameno=119 fix3=0x3c time=15:43
FLEX: State: SYNC2
FLEX: State: DATA
FLEX: Timeout
FLEX: State: SYNC1
FLEX: Locked
FLEX: SyncInfoWord: sync_code=0xb068 baud=1600 levels=4 polarity=POS zero=0.076685 envelope=0.211989 symrate=1602.018163
FLEX: State: FIW
FLEX: FrameInfoWord: cycleno=03 frameno=119 fix3=0x00 time=15:43
FLEX: State: SYNC2
FLEX: State: DATA
FLEX: Timeout
FLEX: State: SYNC1
FLEX: Locked
FLEX: SyncInfoWord: sync_code=0xb068 baud=1600 levels=4 polarity=POS zero=0.055916 envelope=0.213103 symrate=1599.705882
FLEX: State: FIW
FLEX: FrameInfoWord: cycleno=03 frameno=120 fix3=0x00 time=15:45
FLEX: State: SYNC2
FLEX: State: DATA
FLEX: Phase A Fixed 1 errors @ 0x00000001 (0x46f529c4 -> 0x46f529c5)
FLEX: Phase A Fixed 2 errors @ 0x02080000 (0x79de2945 -> 0x7bd62945)
FLEX: Phase A Fixed 2 errors @ 0x00400001 (0x562d9ba0 -> 0x566d9ba1)
FLEX: Phase A Data corruption - Unable to fix errors.
FLEX: Garbled message at block 42
FLEX: Phase B Fixed 2 errors @ 0x00200080 (0x6d60048b -> 0x6d40040b)
FLEX: Phase B Fixed 1 errors @ 0x00080000 (0x00080000 -> 0x00000000)
FLEX: Phase B Data corruption - Unable to fix errors.
FLEX: Garbled message at block 2
FLEX: State: SYNC1
FLEX: SyncInfoWord: sync_code=0xdea0 baud=3200 levels=4 polarity=NEG zero=0.010384 envelope=0.278784 symrate=1596.390817
FLEX: State: FIW
FLEX: Phase F Fixed 1 errors @ 0x00000020 (0x71f67a14 -> 0x71f67a34)
FLEX: FrameInfoWord: cycleno=03 frameno=122 fix3=0x2c time=15:48
FLEX: State: SYNC2
FLEX: State: DATA
FLEX: Phase A Data corruption - Unable to fix errors.
FLEX: Garbled message at block 1
FLEX: Phase B Fixed 1 errors @ 0x00002000 (0x00002000 -> 0x00000000)
FLEX: Phase B Data corruption - Unable to fix errors.
FLEX: Garbled message at block 1
FLEX: Phase C Data corruption - Unable to fix errors.
FLEX: Garbled message at block 0
FLEX: Phase D Data corruption - Unable to fix errors.
FLEX: Garbled message at block 0
FLEX: State: SYNC1
FLEX: SyncInfoWord: sync_code=0xdaa0 baud=3200 levels=4 polarity=NEG zero=0.028525 envelope=0.278633 symrate=2100.604505
FLEX: State: FIW
FLEX: Phase F Fixed 2 errors @ 0x00000801 (0x63df7b1d -> 0x63df731c)
FLEX: Bad Checksum 0x7
FLEX: State: SYNC1
FLEX: SyncInfoWord: sync_code=0xdea0 baud=3200 levels=4 polarity=NEG zero=0.011530 envelope=0.277801 symrate=1973.960374
FLEX: State: FIW
FLEX: Phase F Fixed 1 errors @ 0x00000200 (0x225c7e3c -> 0x225c7c3c)
FLEX: FrameInfoWord: cycleno=03 frameno=124 fix3=0x38 time=15:52
FLEX: State: SYNC2
FLEX: State: DATA
FLEX: Timeout
FLEX: State: SYNC1
FLEX: Locked
FLEX: SyncInfoWord: sync_code=0xdea0 baud=3200 levels=4 polarity=NEG zero=-0.000052 envelope=0.272021 symrate=1598.460775
FLEX: State: FIW
FLEX: FrameInfoWord: cycleno=03 frameno=125 fix3=0x38 time=15:54
FLEX: State: SYNC2
FLEX: State: DATA
FLEX: Timeout
FLEX: State: SYNC1
FLEX: Locked
FLEX: SyncInfoWord: sync_code=0xdea0 baud=3200 levels=4 polarity=NEG zero=-0.009385 envelope=0.272017 symrate=1593.712871
FLEX: State: FIW
FLEX: Phase F Fixed 1 errors @ 0x10000000 (0x7fdc7e3a -> 0x6fdc7e3a)
FLEX: FrameInfoWord: cycleno=03 frameno=126 fix3=0x38 time=15:56
FLEX: State: SYNC2
FLEX: State: DATA
FLEX: Timeout
FLEX: State: SYNC1
FLEX: Locked
FLEX: Timeout
FLEX: Locked
FLEX: Timeout
FLEX: Locked
FLEX: SyncInfoWord: sync_code=0xdea0 baud=3200 levels=4 polarity=NEG zero=0.047657 envelope=0.271265 symrate=1602.925532
FLEX: State: FIW
FLEX: FrameInfoWord: cycleno=04 frameno=006 fix3=0x3c time=16:11
FLEX: State: SYNC2
FLEX: State: DATA
FLEX: Timeout
FLEX: State: SYNC1
FLEX: Locked
FLEX: Timeout
FLEX: Locked
FLEX: SyncInfoWord: sync_code=0xdea0 baud=3200 levels=4 polarity=NEG zero=0.055968 envelope=0.269750 symrate=1596.875000
FLEX: State: FIW
FLEX: Phase F Fixed 1 errors @ 0x00000004 (0x42be0840 -> 0x42be0844)
FLEX: FrameInfoWord: cycleno=04 frameno=008 fix3=0x3c time=16:15
FLEX: State: SYNC2
FLEX: State: DATA
FLEX: Phase A Data corruption - Unable to fix errors.
FLEX: Garbled message at block 1
FLEX: Phase B Fixed 1 errors @ 0x00000002 (0x00000002 -> 0x00000000)
FLEX: Phase B Fixed 2 errors @ 0x00000480 (0x57bc2ad5 -> 0x57bc2e55)
FLEX: Phase B Data corruption - Unable to fix errors.
FLEX: Garbled message at block 4
FLEX: Phase C Fixed 2 errors @ 0x01000010 (0x593fff91 -> 0x583fff81)
FLEX: Phase C Data corruption - Unable to fix errors.
FLEX: Garbled message at block 2
FLEX: Phase D Data corruption - Unable to fix errors.
FLEX: Garbled message at block 0
FLEX: State: SYNC1
FLEX: SyncInfoWord: sync_code=0xdea0 baud=3200 levels=4 polarity=NEG zero=0.032044 envelope=0.272203 symrate=3086.927109
FLEX: State: FIW
FLEX: FrameInfoWord: cycleno=04 frameno=009 fix3=0x3c time=16:16
FLEX: State: SYNC2
FLEX: State: DATA
FLEX: Phase A Data corruption - Unable to fix errors.
FLEX: Garbled message at block 0
FLEX: Phase B Fixed 1 errors @ 0x00000800 (0x00000800 -> 0x00000000)
FLEX: Phase B Fixed 2 errors @ 0x00000048 (0x58a0096a -> 0x58a00922)
FLEX: Phase B Fixed 2 errors @ 0x00800002 (0x54328290 -> 0x54b28292)
FLEX: Phase B Data corruption - Unable to fix errors.
FLEX: Garbled message at block 4
FLEX: Phase C Fixed 1 errors @ 0x00000080 (0x4bec6a97 -> 0x4bec6a17)
FLEX: Phase C Fixed 1 errors @ 0x00000004 (0x583fff85 -> 0x583fff81)
FLEX: Phase C Fixed 1 errors @ 0x00010000 (0x2ec982d0 -> 0x2ec882d0)
FLEX: Phase C Fixed 1 errors @ 0x00000800 (0x24000a35 -> 0x24000235)
FLEX: Phase C Fixed 1 errors @ 0x00000010 (0x5e397ad7 -> 0x5e397ac7)
FLEX: Phase C Fixed 2 errors @ 0x00200004 (0x66eeba77 -> 0x66ceba73)
FLEX: Phase C Fixed 2 errors @ 0x00280000 (0x7ea00625 -> 0x7e880625)
FLEX: Phase C Fixed 2 errors @ 0x00000012 (0x2dde5073 -> 0x2dde5061)
FLEX: Phase C Data corruption - Unable to fix errors.
FLEX: Garbled message at block 9
FLEX: Phase D Fixed 2 errors @ 0x00009000 (0x0a204a94 -> 0x0a20da94)
FLEX: Phase D Fixed 1 errors @ 0x40000000 (0x183fff81 -> 0x583fff81)
FLEX: Phase D Fixed 1 errors @ 0x04000000 (0x20000235 -> 0x24000235)
FLEX: Phase D Data corruption - Unable to fix errors.
FLEX: Garbled message at block 4
FLEX: State: SYNC1
FLEX: Timeout
FLEX: Locked
FLEX: SyncInfoWord: sync_code=0xdea0 baud=3200 levels=4 polarity=NEG zero=0.023369 envelope=0.279507 symrate=1594.528585
FLEX: State: FIW
FLEX: Phase F Fixed 1 errors @ 0x10000000 (0x7ebe0c40 -> 0x6ebe0c40)
FLEX: FrameInfoWord: cycleno=04 frameno=012 fix3=0x3c time=16:22
FLEX: State: SYNC2
FLEX: State: DATA
FLEX: Phase A Fixed 2 errors @ 0x00600000 (0x0800140b -> 0x0860140b)
FLEX: Phase A Data corruption - Unable to fix errors.
FLEX: Garbled message at block 1
FLEX: Phase B Fixed 2 errors @ 0x00802000 (0x00802000 -> 0x00000000)
FLEX: Phase B Fixed 2 errors @ 0x00000210 (0x78000000 -> 0x78000210)
FLEX: Phase B Data corruption - Unable to fix errors.
FLEX: Garbled message at block 2
FLEX: Phase C Data corruption - Unable to fix errors.
FLEX: Garbled message at block 0
FLEX: Phase D Fixed 2 errors @ 0x00000030 (0x00000030 -> 0x00000000)
FLEX: Phase D Fixed 2 errors @ 0x00100004 (0x337af7ab -> 0x336af7af)
FLEX: Phase D Fixed 2 errors @ 0x01010000 (0x2b222b9e -> 0x2a232b9e)
FLEX: Phase D Fixed 1 errors @ 0x01000000 (0x01000000 -> 0x00000000)
FLEX: Phase D Fixed 2 errors @ 0x08000100 (0x3ff5362b -> 0x37f5372b)
FLEX: Phase D Fixed 2 errors @ 0x00005000 (0x11000004 -> 0x11005004)
FLEX: Phase D Fixed 1 errors @ 0x00100000 (0x00100000 -> 0x00000000)
FLEX: Phase D Fixed 2 errors @ 0x00a00000 (0x00a00000 -> 0x00000000)
FLEX: Phase D Data corruption - Unable to fix errors.
FLEX: Garbled message at block 9
FLEX: State: SYNC1
FLEX: SyncInfoWord: sync_code=0x9ea0 baud=3200 levels=4 polarity=NEG zero=0.000125 envelope=0.278918 symrate=2560.212151
FLEX: State: FIW
FLEX: Phase F Fixed 1 errors @ 0x00000200 (0x321e0f4f -> 0x321e0d4f)
FLEX: FrameInfoWord: cycleno=04 frameno=013 fix3=0x3c time=16:24
FLEX: State: SYNC2
FLEX: State: DATA
FLEX: Phase A Fixed 2 errors @ 0x10004000 (0x5ff269eb -> 0x4ff229eb)
FLEX: Phase A Data corruption - Unable to fix errors.
FLEX: Garbled message at block 1
FLEX: Phase B Fixed 2 errors @ 0x0000000a (0x50802000 -> 0x5080200a)
FLEX: Phase B Data corruption - Unable to fix errors.
FLEX: Garbled message at block 1
FLEX: Phase C Fixed 1 errors @ 0x00000040 (0x73e0083c -> 0x73e0087c)
FLEX: Phase C Fixed 2 errors @ 0x04002000 (0x2caf22d1 -> 0x28af02d1)
FLEX: Phase C Fixed 2 errors @ 0x0000000c (0x1ff01f4f -> 0x1ff01f43)
FLEX: Phase C Fixed 2 errors @ 0x20001000 (0x27372bdf -> 0x07373bdf)
FLEX: Phase C Fixed 2 errors @ 0x02000800 (0x56096dcd -> 0x540965cd)
FLEX: Phase C Fixed 2 errors @ 0x22000000 (0x7ee00691 -> 0x5ce00691)
FLEX: Phase C Data corruption - Unable to fix errors.
FLEX: Garbled message at block 8
FLEX: Phase D Fixed 2 errors @ 0x00200200 (0x01403048 -> 0x01603248)
FLEX: Phase D Fixed 2 errors @ 0x00001010 (0x017da148 -> 0x017db158)
FLEX: Phase D Data corruption - Unable to fix errors.
FLEX: Garbled message at block 2
FLEX: State: SYNC1
FLEX: SyncInfoWord: sync_code=0xb068 baud=1600 levels=4 polarity=POS zero=-0.042682 envelope=0.235873 symrate=2337.173232
FLEX: State: FIW
FLEX: FrameInfoWord: cycleno=04 frameno=015 fix3=0x00 time=16:28
FLEX: State: SYNC2
FLEX: State: DATA
FLEX: Timeout
FLEX: State: SYNC1
FLEX: Locked
FLEX: SyncInfoWord: sync_code=0xdea0 baud=3200 levels=4 polarity=POS zero=-0.197583 envelope=0.198227 symrate=1600.049702
FLEX: State: FIW
FLEX: FrameInfoWord: cycleno=04 frameno=016 fix3=0x3c time=16:30
FLEX: State: SYNC2
FLEX: State: DATA
FLEX: Phase A Data corruption - Unable to fix errors.
FLEX: Garbled message at block 0
FLEX: Phase B Data corruption - Unable to fix errors.
FLEX: Garbled message at block 0
FLEX: Phase C Fixed 1 errors @ 0x00004000 (0x00004000 -> 0x00000000)
FLEX: Phase C Fixed 2 errors @ 0x04008000 (0x04008000 -> 0x00000000)
FLEX: Phase C Fixed 1 errors @ 0x20000000 (0x20000000 -> 0x00000000)
FLEX: Phase C Fixed 2 errors @ 0x00020200 (0x00020200 -> 0x00000000)
FLEX: Phase C Fixed 2 errors @ 0x00800004 (0x00800004 -> 0x00000000)
FLEX: Phase C Fixed 1 errors @ 0x00002000 (0x00002000 -> 0x00000000)
FLEX: Phase C Data corruption - Unable to fix errors.
FLEX: Garbled message at block 73
FLEX: Phase D Data corruption - Unable to fix errors.
FLEX: Garbled message at block 0
FLEX: State: SYNC1
FLEX: SyncInfoWord: sync_code=0xcea1 baud=3200 levels=4 polarity=POS zero=-0.043730 envelope=0.273448 symrate=1895.543820
FLEX: State: FIW
FLEX: Phase F Data corruption - Unable to fix errors.
FLEX: Unable to decode FIW, too much data corruption
FLEX: State: SYNC1
FLEX: Timeout
FLEX: Locked
FLEX: Timeout
FLEX: Locked
FLEX: Timeout
FLEX: Locked
FLEX: SyncInfoWord: sync_code=0xdea0 baud=3200 levels=4 polarity=NEG zero=0.015440 envelope=0.269566 symrate=1595.292369
FLEX: State: FIW
FLEX: FrameInfoWord: cycleno=04 frameno=029 fix3=0x38 time=16:54
FLEX: State: SYNC2
FLEX: State: DATA
FLEX: Timeout
FLEX: State: SYNC1
FLEX: Locked
FLEX: SyncInfoWord: sync_code=0xdea0 baud=3200 l
I've upped the -g, lowered the -g , used auto gain ie: no -g setting.. either I get nothing till the gain is upped enough to get a signal and then just the above garbage...

I have COMMERCIAL ANTENNAS outside (25 ft in the air, above the local scrub, low loss cable etc..)same thing.. garbage. Similar tuned antennas direct to the dongle(s), same garbage...

What is any one else using for their secret sauce with rtl_fm to get a good signal into multimon-ng for Flex???? If a P25 9600 4 level control channel and voice is doable and POCSAG1200 is then even a 4 level Flex 6400 signal shouldn't be an issue.

The point of all this is to VERIFY that what goes out on POCSAG1200 and the Flex channels is sent...

I don't have a page tester like the old PE6400 to mess about with this any more, I wish I did... it would put an end to my suffering and headaches! :) ;) :)

I can monitor the signal on another source and its good from the various antennas, strong enough for a pager to trip if sent the data... me no joy.....

Any one got a rtl_fm CLI they'd like to share for Flex????

Thanks!

rtlsdrblog
Site Admin
Posts: 2281
Joined: Mon Nov 19, 2012 11:54 pm

Re: Flex Paging, rtlsdr, rtl_fm, multimon-ng settings. ? ? ?

Post by rtlsdrblog » Thu Jan 31, 2019 12:04 pm

Take a look at the signal in a GUI program like SDR#. Is the signal clean, or are there any interferers nearby?

You're using a sample rate of 22050 Hz. Have a look at the rtl_fm guide http://kmkeen.com/rtl-demod-guide/, and try using a smaller bandwidth. Maybe the problem is that you are receiving neighbouring signals within the bandwidth which could interfere.

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