| Author |
Message |
    
Hoosier Cardinal
| | Posted on Saturday, June 29, 2002 - 11:09 pm: | 
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hello.
I picked up a 139 XLR and a digiscan for 40.00 today but i have a problem. The radio works good on AM but on SSB it is very distorted when the mike gain is opened up past the 7 o clock position. Even with a stock unamplified mike it sounds bad. I bascially got the radio for the digiscan because i want to find a stock clean Robyn 520D to put it on.... |
Deadly Eyes
| | Posted on Saturday, June 29, 2002 - 11:43 pm: |
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Before you go too far try this.....
Have someone else transmit while you listen. Some peoples voices drive their radios much better than others. Perhaps it is just the pure driving power of your voice.
My voice for example is not very good for SSB because I do not have that big deep base quality. I usually have to increase the mike gain to compensate. |
Hoosier Cardinal
| | Posted on Sunday, June 30, 2002 - 1:02 am: |
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I think the radio was "hacked" by some tech wanabee IMHO. I looked at the bottom of the rig with the cover off and i saw plenty of solder traces. Im afraid its been hit by the golden screwdriver.. I really hate when people do this ••••!!! Makes life miserable for the poor guy that gets the radio down the line and then has to have the problems fixed!!!! |
Bigbob
| | Posted on Sunday, June 30, 2002 - 8:14 am: |
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I could be wrong but I think the 139xlr has no limiters from factory,was made before fcc changes,so is dependent on operator for proper modulation. |
Scrapiron63
| | Posted on Sunday, June 30, 2002 - 10:57 am: |
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Even the 23 channel radios had limiters. The 139xlr is a PLL 40 channel. Any of the following will affect the modulation, D-21, D-22, R-78, R84. If it sounds ok on AM, thats probably not your problem. The SSB adjustment is CT-7.
The digit-scans, VFOs and other external variable frequency controls are easy to hook up and work on AM, sometimes SSB is much harder. IF it's not stable on AM, you probably want notice, it could warble around a KC or so, but you will notice it quick on SSB. You might need to check all the connections. The power supplies were weak in some of the older base radios, if its not getting enough voltage, that would make it warble on SB, but still sound ok on am. You might try running it on a good external power supply, that would be a quick and easy check. I've had to do that on some of the old madison bases before. |
Hoosier Cardinal
| | Posted on Sunday, June 30, 2002 - 2:17 pm: |
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Tried the power supplier methind.... No change at all. Still sounds overmodulated and watery on SSB . Ill take it to my tech that is local and see what he can do. If nothing than ill junk the radio and keep the counter. I hate people that screw up radios. |
Scrapiron63
| | Posted on Sunday, June 30, 2002 - 5:48 pm: |
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May not be anything wrong with the radio, just the digit scan hookup. Whoever had it before may not have used SB. You could always take it out, put the radio back orginial, and add channels with a kit or off the chip. |
Hoosier Cardinal
| | Posted on Sunday, June 30, 2002 - 7:17 pm: |
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I dont think its the counter i think its all the radios problem. Someone screwdrivered it bigtime. its going to the tech next week and if he cant fix it its getting the scrapper method.. LOL |
Hoosier Cardinal
| | Posted on Sunday, June 30, 2002 - 8:16 pm: |
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Hey Scrapiron.
I opened it back up again and soldered every thing that i could that looked cut. I then retuned the ALC for the SSB down to about 25 to 30 watts swing with an average of about 18 to 20 with a normal voice peak and it cleaned it right up. Someone peaked the radio to the wall. So now ill see if it holds up any longer but now for some reason the radio wont receive at a distance but up close when i talk on another radio here in the room it receives. Dont get that deal.:-( But at least i know the counter isnt at fault. the radio seems pretty stable with the channel scanner. Ive always liked the old Cobra 139XLR (actually better than the 142) because they talk good on AM and SSB. had one once about 10 years ago and got rid of it. it was the very first really decent base i had and boy did it talk!
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bruce
| | Posted on Monday, July 01, 2002 - 1:58 pm: |
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Im missing something what is a " Kemtron Digiscan" ????? or is it not part of what is going on here. |
Scrapiron63
| | Posted on Monday, July 01, 2002 - 2:50 pm: |
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Hey, your getting there, eliminating one problem at the time. Those old 139XLRs were pretty good old bases. I know a couple guys running them now, they bought them new. The use D-104 mikes, and actually sound much better than some of the newer export radios that people run with too little carrier, too much mod, and echo. I have one guy that I talk to regular, he runs his galaxy base on 1 watt key, since its been opened up all the way, its probably swinging 30-40 watts, and also with some echo, it sounds terrible, the audio just 'rushes' at you, almost like sideband. He can turn up the carrier to 3 or 4 watts, and it sounds much better, but, he likes to watch the meter swing. So whattya going do, just listen and try to figure out what he's saying I guess. |
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