| Author |
Message |
    
Missie
Junior Member
Username: Missie
Post Number: 26
Registered: 10-2006
| | Posted on Tuesday, August 21, 2007 - 11:21 pm: | 
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how can I drop the carrier out put and still keep my moulation on this radio??? thanks |
Dale
Senior Member
Username: Dale
Post Number: 1098
Registered: 12-2002
| | Posted on Wednesday, August 22, 2007 - 5:23 am: |
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vr10 is am power adjustment
vr11 ssb power adjust
vr12 modulation adjust
dale/a.k.a.hotrod
cef426
cvc#64
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Missie
Junior Member
Username: Missie
Post Number: 27
Registered: 10-2006
| | Posted on Wednesday, August 22, 2007 - 11:14 pm: |
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thanks dale!!!!!!!!!! |
Dale
Senior Member
Username: Dale
Post Number: 1103
Registered: 12-2002
| | Posted on Thursday, August 23, 2007 - 5:39 am: |
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np leave me know how it turns out
dale/a.k.a.hotrod
cef426
cvc#64
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Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2615
Registered: 9-2004
| | Posted on Friday, August 24, 2007 - 12:46 am: |
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missie,
you will not find a VR12 in your 148gtl.
in the 2000GTL, VR12 is the AMC because VR7 is used for the modulation meter.
there is no mod. meter in a 148, so they use VR7 for the AMC.
so here's what you want to do.
replace R194 (1k ohm, right behind VR10) with a 1N4001 diode. (you can get these at rad shak)
the banded end goes toward TR41 (mounted to the chassis wall)
if the diodes leads will not fit in the holes for R194, just mount the diode on the solder side of the PC board. observe polarity!
turn VR7 all the way up.
turn dynamike all the way up, key the mic, and while saying "ahhh" into the mic, turn L38 for max. PEP wattage.
(be careful not to break the ferrite core.
if it wont turn, touch the tip of your soldering iron right to the ferrite for a couple of seconds.
then immediately turn the slug back and forth a bit to free it up)
now turn the dynamike all the way down, key the mic, and adjust VR10 for the deadkey you want.
if it wont go low enough, replace R196 with a jumper wire.
if you are planning on running a linear, i would set the deadkey at 2 watts. you should be able to swing up to 18-20 watts PEP.
good luck,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Dale
Senior Member
Username: Dale
Post Number: 1104
Registered: 12-2002
| | Posted on Friday, August 24, 2007 - 5:39 am: |
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im vey sorry missie kid is correct there is no vr12 thats the 2000gtl.again very sorry about that missie.thank-you kv for the correction.
after reading your post kv i went to the mod list here and they dont even have it listed as
the amc adjustment.i honestly thought the 148/2000 had the same vrs
dale/a.k.a.hotrod
cef426
cvc#64
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Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2616
Registered: 9-2004
| | Posted on Saturday, August 25, 2007 - 8:09 pm: |
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i read in a book somewhere that all these MB8719 dual conversion SSB chassis were basiscally the same.
its that word "basically" that gets us.LOL
for example, i was telling someone on here how to do this diode mod in a uniden grant.
i was telling him that the banded end of the diode goes to the right.
in his chassis, the resistor runs front to back.
needless to say, it was a bit confusing for a while.
and it was my assumption that started the problem.
learned my lesson there about guessing.LOL
its kinda funny to think about, that someone with a 2000 GTL might turn up VR7, and think they had loads of modulation because that meter smacks the right side every time they whisper into the mic.LOL
have a fine one,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Missie
Junior Member
Username: Missie
Post Number: 28
Registered: 10-2006
| | Posted on Monday, September 03, 2007 - 1:55 pm: |
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thanks kid I did that, works greate! now I have another QUESTION when doing the recieve mod tr14 change with 2sc2999 which way dose the 2999 go flat side right or left looking at the front of the radio? thanks... |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2617
Registered: 9-2004
| | Posted on Tuesday, September 04, 2007 - 11:51 pm: |
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hi missie,
the flat side/ the one with the 2999 printed on it goes to the left.
the back of the transistor goes toward the big audio transformer.
use the old transistor you just removed from TR14 (2SC1674) and use it to replace TR19.
this will upgrade the SSB detector circuit.
good luck,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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