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Message |
    
Airplane1
Senior Member
Username: Airplane1
Post Number: 1001
Registered: 5-2004
| | Posted on Saturday, July 21, 2007 - 9:18 am: | 
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Hi, is there a way to adjust the modulation on my 2985dx myself?
I was thinking of saying aaahhhhhhhhh into the mic while adjusting it but dont know what pot to turn.
does anyone know which pot and if doing it this way will be ok?
thanks |
Airplane1
Senior Member
Username: Airplane1
Post Number: 1002
Registered: 5-2004
| | Posted on Saturday, July 21, 2007 - 2:23 pm: |
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OH, I forgot to say it is on ssb that I want to get it to have higher modulation. I have a dm-452 mic and opened it up, turned the power up on it all the way and also the mic gain on radio. it still needs more modulation as people have been telling me.
so is there a pot in the radio I can turn all the way up? |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2593
Registered: 9-2004
| | Posted on Saturday, July 21, 2007 - 3:21 pm: |
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VR17.
just turn it all the way one way. if you have little or no modulation; turn it the other way all the way.
as long as you dont turn anything else, you are pretty safe doing this.
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Airplane1
Senior Member
Username: Airplane1
Post Number: 1003
Registered: 5-2004
| | Posted on Sunday, July 22, 2007 - 8:47 am: |
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thank you Kid,
What pot for the SSB Power?
Roger |
Dale
Senior Member
Username: Dale
Post Number: 1020
Registered: 12-2002
| | Posted on Sunday, July 22, 2007 - 9:13 am: |
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kv i was looking all over best i could do was
the 2950/70dx.i see they changed the vr numbers
it used to be vr14 for amc adjustment.
dale/a.k.a.hotrod
cef426
cvc#64
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Airplane1
Senior Member
Username: Airplane1
Post Number: 1004
Registered: 5-2004
| | Posted on Sunday, July 22, 2007 - 11:08 am: |
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Dale, I was looking at the 2950 too cause I could not find the info on the 2985dx, I thought maybe they were the same. |
Dale
Senior Member
Username: Dale
Post Number: 1024
Registered: 12-2002
| | Posted on Sunday, July 22, 2007 - 8:29 pm: |
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are any of them labeled?is there a vr14
dale/a.k.a.hotrod
cef426
cvc#64
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Airplane1
Senior Member
Username: Airplane1
Post Number: 1005
Registered: 5-2004
| | Posted on Tuesday, July 24, 2007 - 2:22 pm: |
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Well I turned the VR17 all the way up and now I have much better control of the modulation with mic gain control and my radio is sounding very loud now with the mic gain at half way.
I did turn the ssb power to show about 35-40 watts when saying aaaahhhhhhhh with rf power all the way up, hope this is ok? I dont know what these radios can do without hurting them.
I turned the am power to dk at 10watts with rf power all the way up and 2watts dk with rf power turned al the way down, I need to re do it because after closeing the radio up it started dking with rf power turned all the way up at 20watts and swinging 22watts, So I did something wrong but I can turn it down to 7watts with the rf power control all the way down but it still swings 22watts, 22watts is ok for a swing I believe.
All reports I get are loud and clear and my signal came up a bit too.
Thanks for the info Kid_vicious, I now know from openning the radio the pots are all labeled on the board what they are for so I will have no trouble setting it up now.
Roger |
Dale
Senior Member
Username: Dale
Post Number: 1030
Registered: 12-2002
| | Posted on Tuesday, July 24, 2007 - 7:56 pm: |
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hmm dont understand why it changed?i usually
dont run alc/ssb power all the way up cause
sometimes ssb will start to warble.as far as audio.i put on a stock mike and adjust mic gain
on radio wide open.and adjust for 100%.while this
may not be the most accurate way but with what
i got to work with about the best i can do.my
reports are always sounding loud and clear.talked
to lon 1 week ago on 11m ssb net report was great
dale/a.k.a.hotrod
cef426
cvc#64
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Airplane1
Senior Member
Username: Airplane1
Post Number: 1006
Registered: 5-2004
| | Posted on Wednesday, July 25, 2007 - 11:07 am: |
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Hi Dale, I get 120% modulation when I turn the mic gain up all the way but I get muffled so I dont run it wide open. I prob could with stock mic.
I might turn the ssb down just a tad yet.
Roger |
Dale
Senior Member
Username: Dale
Post Number: 1033
Registered: 12-2002
| | Posted on Wednesday, July 25, 2007 - 6:13 pm: |
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only turn back ssb if warbling occurts.sounds
to me like audio is just a tad high at 120%
id back it off just a hair and check with
stock mike with mike gain full.
dale/a.k.a.hotrod
cef426
cvc#64
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Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2594
Registered: 9-2004
| | Posted on Thursday, July 26, 2007 - 12:43 am: |
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glad to hear its working!
if it were my radio i would run the SSB at about what the max AM swing is.
for you, you say about 22 watts. i would run the SSB at about 22-25 watts.
its up to you.
the higher deadkey with the cover on thing makes me wonder.
that should not happen.
i would open the radio up, try to turn it back to where it was, then put the cover on with no screws and see if it changes.
did your SWR also change when the power jumped up?
very strange...
anyway, the 2985dx is the 2950dx in a base cabinet.
the 2995dx is the 2970dx.
the 2950dx is different from the 2950. (better!)
you can find the factory service manual and schematics on the internet.
wont be back on the forum until tues. so i will check back then.
later,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Airplane1
Senior Member
Username: Airplane1
Post Number: 1007
Registered: 5-2004
| | Posted on Thursday, July 26, 2007 - 8:14 pm: |
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Well I checked things out inside and readjusted the am to 10 watt dk and put cover back on, it is working ok so I just think I messed with the am pot befor putting cover back on.
It is working great so far and as for the SSB, I turned it to 35 peaking with loud ahhhh and just keep it turned down a little with rf power to about 25 watt peaks and it is not getting hot.
I think it will be all right. Now to tune up the grant xl. I think the recieve on it is a bit low, can I turn a pot to get it a little better without any equipment?
Roger |
Dale
Senior Member
Username: Dale
Post Number: 1035
Registered: 12-2002
| | Posted on Thursday, July 26, 2007 - 9:35 pm: |
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im assumiong 10watt dk is with the rf pwr all the way up.
2 watt all way down
10watt all way up
using the ext.pwr. control.i dont think 35watt
pep will hrt the radio seems the newer ones do more watts,high dk will hurt radio more than
too high pep.souinds like ya got it
dale/a.k.a.hotrod
cef426
cvc#64
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Airplane1
Senior Member
Username: Airplane1
Post Number: 1008
Registered: 5-2004
| | Posted on Sunday, July 29, 2007 - 11:26 am: |
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yea, 10 watt rf power all the way up and 2 watt rf power all the way down.
ssb is peaking at about 35 watts but no issues with the sound quality, getting great reports all around.
it seems I got it tuned up pretty good.
thanks |
Dale
Senior Member
Username: Dale
Post Number: 1039
Registered: 12-2002
| | Posted on Sunday, July 29, 2007 - 12:42 pm: |
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good job.the tune up stuff is posted on the
left of this post for the grantxl
dale/a.k.a.hotrod
cef426
cvc#64
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Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2596
Registered: 9-2004
| | Posted on Tuesday, July 31, 2007 - 11:47 pm: |
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right on airplane1!
sounds like you got 'er done.LOL
to tune the recieve on the grant XL, you will need a small plastic tuning screwdriver, or a toothpick that has been carefully filed to fit in the cans.
no metal or jewelers screwdrivers allowed.
put the radio on ch. 19, RF gain at max., and key up a walkie talkie, other radio, or whatever else you have that will give you a solid signal at less than S-5 on your grant XL.
now adjust L14,12,10,9,8,7,6,5,4 in AM mode for max. S meter reading.
adjust them VERY slowly.
dont adjust any of the other cans.
adjust them again in the same order, as they interact with eachother a bit.
that should do it,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Airplane1
Senior Member
Username: Airplane1
Post Number: 1010
Registered: 5-2004
| | Posted on Wednesday, August 01, 2007 - 8:16 am: |
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Thanks Kid,
Do I turn them to the right or left?
Roger |
Dale
Senior Member
Username: Dale
Post Number: 1050
Registered: 12-2002
| | Posted on Wednesday, August 01, 2007 - 4:39 pm: |
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experiment with them seems sometimes best performance is achieved left sometimes right
as kv stated use some type of radio to get a
signal then watch your s-meter carefully.your
needle will go up and down.kv did you just
give him the ones foe am only?or those
for ssb aswell.if so he needs to know what 1
does ssb so he can switch to that mode
dale/a.k.a.hotrod
cef426
cvc#64
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Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2599
Registered: 9-2004
| | Posted on Thursday, August 02, 2007 - 11:04 pm: |
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even though the service manual states that the radio should be in this mode or that mode, you can tune all of them in AM mode. BUT!!!
some of these cans are for the freq. the radio is on, but some are for the IF and are at 7.8, 10.695, etc.
some are at 455khz!
so you can see, that trying to tune them using the method described above could cause them to be misaligned.
i listed the ones that can be tuned in AM mode, and the peak will be noticable using the above "cheap and dirty" method.
there are other RX coils, and they are the ones with the bigger "flathead" style slug in them.
if you were to try to tune these using, say, a 27.185mhz signal; you would not see the peak, and would not know that it was mistuned.
this is not for all radios, just my experience tuning up alot of these particular radios.
one good thing to do is to get a sharpie, and draw a line across the top of the can indicating the direction of the slug.
that way, if you dont notice a difference when turning the slug, you can put it back.
if you do change the adjustment; wipe off the old line and make a new one, indicating the correct adjustment.
just to clarify;
the suggestions i have made so far are not the "correct" way of doing an alignment.
you need a signal generator to do it right.
the thing is, you can get it very close using the "wrong" way.
i would only do this to my own radios that i didnt care if they ended up worse off then when i started.
just my little disclaimer.LOL
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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