SOME 900 RADIOS SOUND STRANGE

[N4KVE]

I'm putting this in the 900 section as this only applies to my Motorola 900 radios. I started off talking on a local 900 ham repeater [Tait equipment] by purchasing a couple of GTX portables. While they don't have many features, they sound the best of all the 900 radios I have. I also have a GTX 30 watt mobile, which also sounds great. I picked up a few 900 Jedi radios, & they work fine, but the GTX radios just sound a bit better. Later on I got a 9250 which was owned by a tech, & aligned to factory spec, but the rx sounded wierd. Great rx sens, but sounded off freq. It was checked, & in spec. I sold it & got another Jedi. So I figured it was time to upgrade to a Spectra mobile. 30 watts, highest firmware, D37KGA5JB5FK model #, etc, but the radio sounds exactly like the 9250. The black decal doesn't say "hearclear". so I wonder if the radio has that option. Some users sound muffled, while others sound OK. If I listen on the UHF link, everyone sounds great. While I can't check, the person who sold me this radio verified it's in spec. Is it possible the Spectra is set for "hearclear" on all the freq's, & this is why people sound funny on the "non hearclear" repeater. I haven't had the radio long enough to travel near other repeaters, so I don't know if they sound weird also. I don't have an old laptop, so I can't verify any of the settings on the Spectra. So why do the "less feature rich" GTX radios sound the best? Why do the 9250, & Spectra both have the same funny rx sound? Is this just the way narrow band 900 sounds, or a "hearclear" mismatch? Until I figure this out, I put the GTX back in my car. Oh, and a Kenwood TK 481 portable sounds fine on the same repeater. Also, I have never listened to any of these 900 radios on a true 900 commercial repeater, just amateur. Any help here? GARY N4KVE

[kcbooboo]

From what I recall, there were several decal styles used: silver letters with black background, brown letters with white background, and probably some I have never seen. Not all the HearClear-equipped radios were marked as such. Assuming the model numbers are correct, the D37...B5.. would have a separate HearClear board plugged into the front-left corner of the command board. The E-series radios have a completely different command board: no MLM but HearClear is built into it. The only way to know for sure is to pop the top cover off and look at the command board.

Some radios call it HearClear. Others call it Companding. Others might call it compression/expansion. Others call it Flutter-Fighter. It's all a marketing thing. Somehow the systems are fairly compatible but every radio in the system has to use it or not use it for things to sound good and work the way it was designed.

Bob M.

[N4KVE]

Thanks for the reply. I'll have to have somebody read the radio to verify, but judging from the way the radio sounds, it seems hearclear is on, but should be off. Happy new year. GARY N4KVE