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I don't know how many will care about this but I built a box and thought I'd post it. For the woodworkers here, please ignore the joints. I used the miter corner "tape trick" instead of clamping and the thing blew up on me during glue up and I had to scramble for clamps. Didn't get my usual, clean corners. I was also too lazy to route the edges.

Yes, that is why I carry the mobile UHF in the car. Sometimes I'll carry the 7550e UHF if I am going out and about with the family, so we can talk via GMRS... but... We should probably start a new thread, hijacking a CCR thread to post about pros/cons of Motorola/Kenwood/ICOM et. all radios is probably not going to fly well with the moderators. DONE: https://forums.mygmrs.com/topic/2183-brand-name-radios-proscons-thread-usednew/ G.

Oh, dang... I am very very sorry if I came out that way. Just trying to help, that's all, sometimes I get too passionate about it... So, there is a plethora of older Motorola (and other brands) radios to chose from, to my mind first comes the workhorse HT1000, the radio that public safety used to carry back when I was in college, or the HT1250s, both of those are good radios to own, but if you want to do the newer digital VHF/UHF ham radio stuff, the newer XPR series offers DMR and FM, although only single band. The APX radios (more $$$) will do more than one band, but in P25. The XTS will also do P25... which is not compatible with DMR (or MotoTRBO) unfortunately, although some people build MMDVMs that will link P25 repeaters to DMR, or D-Star, or Fusion... et. all. In my experience, once you get past the "single band" psicological barrier, b/c most of the LMR stuff is going to be single band, I think you won't ever look back. I will say that, b/c for me at least it was a very hard pill to swallow at first. I've always carried dual band radios on me for more than a decade... But been carrying a single band radio for a year or so now and never looked back. Most of the time on my belt is a VHF XPR6550, but I have two mobiles, one VHF and one UHF in the car to reach the other band. You might ask why VHF? well, I found it to be much further reaching than UHF, has HAM VHF repeaters, has MURS in case you need simplex, plus Marine VHF along with the NOAA weather channels to which I listen. Then there is a host of EMS/Public safety stuff on VHF too, like Dane County EMS, etc, which is all VHF FM still. All Police Depts around here went digital circa 2017 IIRC, most of them are P25 now. I found the XPR6550 to be a really good radio for the cost. I have a few of those, in both flavors, U and V. You can find those for < 100 bucks on eBay from time to time, and the CPS can be purchased on eBay as well, along with the XPR programming cable. The APX/XTS/XTL radios I don't know much about, but I've spoken with people who swear by them, so I figured those are worth a look too. There are a lot of <100 buck used radios that are way better than most CCRs. ICOM and Kenwood make a lot of decent stuff too, some of the newer Kenwood NX-series radios will do P25 and DMR on the same radio... and while Motorola won't, the audio overall sounds better, IMO, of course. The RX Audio Leveling function available on the XPR7000 series and XPR5000 series is probably the best feature I've ever encountered in a radio... which basically makes every incoming transmission sound exactly the same volume, regardless of the other person having the gain on their mic set to +30 dB... So you never have to reach for the volume level ever again... Feel free to PM me. G.

I believe hes mentioning CTCSS and DCS codes, which have been gone over extensively in the forums. R-tone and T-tone. Not exactly sure how they'll be labeled but I do recall it saying R and T before the setting for Receive and Transmit

Thank you all for the information. I haven't heard of the Golay code/algorithm.... I will have to look that up. LoL.... I am acquainted with Gray code, BCD code, and binary coded octal.... Used to work with come navigation equipment that was nearly as ancient as I. The telemetry monitoring unit we used during preflights had nixie tube displays. We used thumbwheels to dial in hexadecimal addresses to display. Some outputs were in octal and we had to convert the octal numbers to decimal forms of radians and then convert the radians to degrees.... Good ole days...

I am online now, and have asked for Signal Report...nothing heard (my simplex radio is not picking up the signal, so I know I'm NOT hitting a repeater, also no repeater trailer sound at all).

DCS is transmitted at a rate of 134.4 bits/s. The DCS waveform directly modulates the FM carrier, with a logic 1 represented by a positive carrier shift and a logic 0 represented by a negative carrier shift. The FM deviation is about the same as CTCSS/PL. The DCS waveform's edge rates are carefully controlled to limit harmonic content to avoid generating audible harmonics. A DCS word consists of a 23 bit cyclic Golay code with 12 bit codeword (23,12) formed from the 12 least significant bits. The 11 most significant bits are error correcting code bits generated by the Golay algorithm from the 12 codeword bits. The 12 bit codeword consists of a fixed Octal 4 (100 binary) plus the 3 Octal digits that you can program. A DCS word plays out backwards over the air due to the least significant bit being transmitted first. A DCS word is sent repeatedly as a continuous low baud rate data stream. DCS/DPL has a specific turn-off code or reverse burst at the end of a transmission which resembles a 134.4Hz sine wave. In radio systems with a mix of CTCSS/PL and DCS/DPL usage, it is recommended to avoid using a CTCSS/PL tone of 136.5Hz due to the DCS/DPL kerchunk problem caused by the 134.4Hz DCS reverse burst. The time required to reliably decode DCS is slightly longer than CTCSS and is about 350ms or less. CTCSS typically decodes in about 250ms or less. When decoding DCS on very weak signals, the DCS decode threshold can be as much as 2 dB worse than CTCSS. From an end user perspective, these differences are way down in the noise (LOL) and it's hard to tell any difference. The average end user probably won't notice any difference in DCS/DPL vs. CTCSS/PL performance. DCS has its own set of issues to deal with. The long high and low bit times of the NRZ data can cause problems with baseline wander and cause decode problems. Distortion in the transmitted DCS waveform itself can cause decoding problems in the receiver. DCS is also sensitive to frequency errors in the transmitter and receiver. A signal transmitted with DCS received a few kHz off-frequency in the receiver impresses a DC offset on the recovered DCS waveform which causes the decoder to see a step function instead of the DCS data. This causes very slow decoding or failure to decode. Good low frequency response down to about 3 Hz in the modulator in the transmitter and in the discriminator output in the receiver are necessary for reliable DCS operation. IIRC phase modulated systems have trouble with DCS. True FM modulated systems tend to work better. Motorola trademarked the Digital Private Line (DPL) name. Other manufacturers have to call it something else. Digital Coded Squelch (DCS) is the generic name. You'll see mixed usage of the two names as I have used them above. If it's not a Motorola radio, it's not DPL. It's DCS instead even though it's exactly the same thing as DPL. Motorola originally implemented 83 DPL codes and manufacturers have expanded the set of codes to 104 codes. Motorola's 83 DPL codes have been implemented by all manufacturers but not all manufacturers have implemented the full set of 104 codes. Motorola's original set of 83 DPL codes have been fully vetted and are known to work well. Some of the extra codes making up the set of 104 codes may not work as well. YMMV. I've also heard DPL sometimes referred to as "Definitely Prevents Losers". LOL. I successfully thwarted a GMRS repeater jammer years ago with DCS/DPL so the jammer couldn't key my repeater. The jammer didn't have a clue about DCS/DPL nor did he have DCS/DPL capability in his antiquated equipment and only had CTCSS/PL. The jammer eventually gave up. This trick won't work anymore given that practically all manufacturers now offer DCS capability in their radios. DCS information: https://wiki.radioreference.com/index.php/DCS http://onfreq.com/syntorx/dcs.html http://www.repeater-builder.com/tech-info/ctcss/ctcss-overview.html

Note that on an FM or Phase modulated radio all transmissions are analog. Digital data is actually represented by the presence or absence of an audible or sub-audible tone. IIRC 131.4hz is used for DCS. If the signal frequency is not stable, the DCS sub-tone will also vary, making detection of the bitstream difficult or impossible.

CTCSS is older and more prone to spurious noise opening the squelch - weather or ambient. Additionally, there are relatively few usable tones. DCS is newer was was designed to address those shortcomings. Both came out of Motorola, who initially was one of the only manufacturers of radios with enough frequency stability to use DCS (though others caught up quickly). Even today, some Baofeng as they age have trouble with a DCS system. Also, many older radios can't use DCS at all, and a few transitional models needed modules to enable it (usually you'd swap our the CTCSS module to a dual mode module). So, yes, DCS is better, but CTCSS more compatible.