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Message |
    
Big_rigger
Member
Username: Big_rigger
Post Number: 62
Registered: 8-2005
| | Posted on Friday, June 22, 2007 - 1:16 am: | 
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the recieve soundsoff freq, can some one tell me how to put back in line |
Hyperno_1979
Intermediate Member
Username: Hyperno_1979
Post Number: 358
Registered: 12-2005
| | Posted on Friday, June 22, 2007 - 7:21 am: |
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Only info i have is for 8719 Grant.
USB Freq: CT1
LSB Freq: L22
AM Freq: L23
TX Freq: VR5
I am still on the hunt for more info on the 858 pll.
Cheers,
Bob.
CEFFFCEF
Bob
CEF703/CVC26
269 Hunter Valley
27.355 lsb.
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Tech237
Moderator
Username: Tech237
Post Number: 829
Registered: 4-2004
| | Posted on Friday, June 22, 2007 - 6:02 pm: |
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Bob, I'll look in my books and see what I have on the 858
Simon
Tech237
N7AUS
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Yankee
Senior Member
Username: Yankee
Post Number: 1457
Registered: 7-2003
| | Posted on Saturday, June 23, 2007 - 11:05 am: |
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Depends on which Grant you're speaking of. One was made by Uniden for President in the 70s & 80s and the other is a much newer export model. On the other hand you also have the Uniden Grant XL and LT, therefore that makes four models of the Grant.
I have the Sams Photofacts the has the same chassis that the original President Grant has in it.
The Sams I have is number 179 dated March 1978.
Carl CEF-357
CVC-9 HAM-28
Flatlands of Oklahoma
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Big_rigger
Member
Username: Big_rigger
Post Number: 63
Registered: 8-2005
| | Posted on Saturday, June 23, 2007 - 1:57 pm: |
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thanks everbody the grant is older one |
Guardian
Member
Username: Guardian
Post Number: 51
Registered: 5-2004
| | Posted on Saturday, June 30, 2007 - 2:18 pm: |
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ok i have a president grant and when i key the mic i get static with no voice so is that the audio amp or is it one of the finals please help Thanks Doug |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2568
Registered: 9-2004
| | Posted on Saturday, June 30, 2007 - 8:56 pm: |
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two guesses for you guardian.
if its the old grant with the upd858 chip in it, then try replacing C179 with a 2.2uF 25volt electrolytic capacitor. watch the polarity.
if its the mb8719 chassis, and it works on SSB; then try replacing TR41 with an NTE152 or a 2N6487. either will work.
these are assuming that you know the mic is working by trying a second mic on the radio.
also, do you have a wattmeter?
what is it telling you?
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Guardian
Member
Username: Guardian
Post Number: 52
Registered: 5-2004
| | Posted on Sunday, July 01, 2007 - 2:48 am: |
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ok i got it to key up on ssb but not on AM and there were extra channels put in off the mb8719 chip. Doug |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2570
Registered: 9-2004
| | Posted on Sunday, July 01, 2007 - 11:31 pm: |
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if by "key up" you mean that you got modulation on SSB, but just a dead carrier with no modulation on AM; then try replacing TR41 like i mentioned above.
a dead carrier will show wattage on a wattmeter, but the wattage will not increase when you talk into the mic.
if you have a modulation meter, its easy to see whether or not you are modulating the carrier.
good luck,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Guardian
Member
Username: Guardian
Post Number: 54
Registered: 5-2004
| | Posted on Saturday, July 07, 2007 - 7:55 pm: |
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ok the grant i have is the one that takes the single driver and final when i transmit on AM it sounds like i am on a different channel but on SSB it sounds on Freq. could it be tha drive final is bad it had a 1969 and a 1306 in it and i put a 2312 and a 1969 in it . any help would be great .Thanks Guardian |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2573
Registered: 9-2004
| | Posted on Saturday, July 07, 2007 - 9:10 pm: |
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the 1969, and the 2312 are both finals.
they cannot be used as a driver.
the 1306 is a driver, as is the 2SC2166.
for best performance, replace the driver with a 2SC2166, and the final with a 2SC1969.
then re-bias them for 30mA for the driver, and 60mA for the final.
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Guardian
Member
Username: Guardian
Post Number: 55
Registered: 5-2004
| | Posted on Sunday, July 08, 2007 - 10:35 am: |
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How do i re-bias them can u walk me through the process that would be great we do not have a repair shop for cb radios in Spokane Wa any more .Thanks Guardian |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2576
Registered: 9-2004
| | Posted on Sunday, July 08, 2007 - 10:26 pm: |
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sure thing,
3. ch.19USB mike gain at minimum.
insert DC ammeter at TP8. (driver bias)
this means that you need your DC volmeter set to milliamps on a scale that can read 200ma (milliamps).
this hook up is not the same as voltage testing! when you test for current, you hook the voltmeter in series with the lead under test.
so, pull the wire off of TP8, and clip the negative lead to the end. touch the positive lead to TP8. key the mic and adjust VR9 for 30ma.
reconnect the wire to TP8.
4. ch.19USB mike gain at minimum
pull wire off of TP7 and clip negative lead of voltmeter to it.
touch positive lead to TP7.
key the mic and adjust VR8 for 60ma.
reconnect the wire to TP7.
(TP7&8 are right next to eachother, near the audio chip in front of the transformer)
thats it!
go slow and stop if you have more questions,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Guardian
Member
Username: Guardian
Post Number: 57
Registered: 5-2004
| | Posted on Monday, July 09, 2007 - 8:14 pm: |
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where would i look for the tr 41 i found all the other ones but can not seem to find that one any help would be great thanks Doug |
Guardian
Member
Username: Guardian
Post Number: 58
Registered: 5-2004
| | Posted on Monday, July 09, 2007 - 8:17 pm: |
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and if any one has a layout they could send me or tell me where i can go .Doug |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2578
Registered: 9-2004
| | Posted on Tuesday, July 10, 2007 - 12:09 am: |
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TR41 is sometimes labeled Q41, depending on what model radio you have.
with the component side up, with the knobs facing you; TR41 will be in the rear right corner, just to the rear of the audio chip.
it is mounted to the side of the chassis just like the audio chip (TA7222AP) is.
so if you look along the outside of the chassis to the rear of the audio chip, you will see the end of the bolt that holds TR41 in place sticking out just a bit.
when replacing this transistor, its much easier if you very carefully cut all the little cable ties on that big bundle of wires before you start.
that way you can move them out of your way while working.
just be sure to put new cable ties on after you are done. try to make the wire bundle look just like it did before you started.
be sure to use an insulator, and some new heatsink grease when installing the NTE152 or 2N6487, whichever one you choose.
good luck,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Guardian
Member
Username: Guardian
Post Number: 59
Registered: 5-2004
| | Posted on Tuesday, July 10, 2007 - 12:38 pm: |
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ok how can i turn down the power on the grant to get more swing and how do i put in extra ch it has the mb8719 pll i think some one tried and did not know what they were doing .Doug |
Guardian
Member
Username: Guardian
Post Number: 60
Registered: 5-2004
| | Posted on Tuesday, July 10, 2007 - 1:07 pm: |
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ok i dont know if it makes a diference but the grant i have is the one tha has the pc-409 board and when i looked for tr41 or q41 i found r193 is tha what i ned to replace. Doug |
Guardian
Member
Username: Guardian
Post Number: 61
Registered: 5-2004
| | Posted on Tuesday, July 10, 2007 - 2:00 pm: |
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ok is the driver the one closes to the out side of the radio or is that the final still tring to get this grant up and running guardian |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2580
Registered: 9-2004
| | Posted on Tuesday, July 10, 2007 - 10:58 pm: |
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VR10 is the AM power control.
as for channel mods and swing mods; they are all over this forum and all over the net.
just do a search for "148gtl mods" or 2000gtl mods" or "grant xl mods" etc...
you will find lots of info.
R193 is a resistor, and is not what you are looking for.
you are looking for a transistor that looks just like the final and driver, but has a different part number on it.
the part number probably says "C1419" or "D1135", or something like that.
it is mounted to the metal wall of the chassis, so it shouldnt be too hard to find.
here's another way.
look at the solder side of the radio (the green side) with the knobs facing you. look at the rear left corner.
see that big screw that holds the PC board in place?
see the notch in the PC board right in front of it with the three legs coming out of it?
thats TR41.
looking at the rear of the chassis with the component side up; the driver is the one on the left.
it is probably labeled C2166 or C1306.
the final is probably labeled C1969.
good luck,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Guardian
Member
Username: Guardian
Post Number: 62
Registered: 5-2004
| | Posted on Wednesday, July 11, 2007 - 3:28 pm: |
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what other driver besides the 2166 and the 1306 can be used with the 1969 final. guardian |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2583
Registered: 9-2004
| | Posted on Wednesday, July 11, 2007 - 10:01 pm: |
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you can use an NTE235, but they are not as reliable as the 2SC2166.
it really shouldnt be a problem to get a 2SC2166. they are available through at least 5 different CB websites, and on ebay.
pretty cheap too.
if you are trying to find out if a driver you have lying around will work, then do a search for the part number, and then do one for the 2166.
if the leads are the same (E,B,C) then it might work.
good luck,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Guardian
Member
Username: Guardian
Post Number: 63
Registered: 5-2004
| | Posted on Saturday, July 14, 2007 - 3:34 pm: |
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ok matt i replaced both the final and driver and the tr41 and the radio still sound the same on the AM side . now i am at a lose as to were to look now .any ideas .Doug |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2585
Registered: 9-2004
| | Posted on Saturday, July 14, 2007 - 6:07 pm: |
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doug,
i was looking through this thread to find out what the original issue you posted about was, and it seems like you havent really described what the radio is doing in detail yet.
you said it sounds like you are on another channel, and also that you only get static when you key up on AM.
would you expound upon this please?
i need more info.
i will say that at this point, it gets pretty tough to find the problem without any test equipment. you really need a freq. counter, a sig. generator, and a voltmeter to troubleshoot this problem.
the reason i start with the semiconductors is because they are the most likely parts to go bad.
usually, they go bad before the peripheral parts around them blow.
without any test equipment, its cheap enough to try to replace these parts, and its good practice.
my GUESS is that it might be a bad electrolytic capacitor. (people that read my posts alot are probably laughing at me right now because i ALWAYS say that!)LOL
but seriously, this chassis has some caps that are barely rated for the voltage they are used at, and with age, tend to go bad, causing problems just like the one you are having now.
if it were MY radio, i'd just replace all 60+ electrolytic caps and be done with it, but i have them lying around, so its free.
probably costs 30-35 dollars for all the caps.
anyway, try C18, C95, and C174.
just guesses, but they could cause this problem.
replace them with 16-25 volt caps, and if you cant find the right values (uF) then going a bit higher is ok. dont go lower, and try to stay really close.
this goes only for these three caps. any others should be replaced with the same value.
(except C172, which should be replaced with a 2200uF 25 volt cap.
again, these are just guesses, so if you want to mess with it, you can try these, but you could be on a wild goose chase without the test equip.
best of luck,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Guardian
Member
Username: Guardian
Post Number: 64
Registered: 5-2004
| | Posted on Sunday, July 15, 2007 - 3:38 pm: |
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Ok i will see if i can word this the right way. ok i picked up this radio from a friend and when i hooked it up on the AM side it sounds like the mic is wired wrong so i changed mics and it still sounds like i am on a diferent ch and i have replaced both the final and driver and also the TR-41 and it still sounds like i am on a diferent ch i know the mic is good cuase it works on another radio but on this one it sound bad also when i am on ssb it sound ok i had a radio check from some one and they said it sounded good but on AM it dont. I am wanting to get it up and running so i can use it in my truck so i can have ssb in there so if this helps you with any ideas let me know ok thanks matt for your help maybe someone out there can help me out too .Thanks again Guardian. |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2586
Registered: 9-2004
| | Posted on Sunday, July 15, 2007 - 11:58 pm: |
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good luck with getting a tech to help you on this forum.
so, have you personally heard what your radio sounds like on AM from a distance?
because it sounds to me like the only reference you have so far is someone else's opinion, and we all know what those are like...
i still dont know what "sounds like im on another channel" means. was this something someone else told you? or is this your observation?
sorry, but without some test equip. to see what freq. your radio is transmitting on, there's not much more i can tell you to try.
any of the adjustments that might need tuning require this equip. to get it right.
the only guess i can make at this point is to try turning VR5 a bit at a time to see if the TX sound on AM improves.
VR5 adjusts the TX freq. for the AM mode. (if the clarifier has not been unlocked)
you really should have a freq. counter to set it, but you might get it close by trial and error.
just make a note of its original position so you can put it back if it doesnt help.
buying a freq. counter or sending the radio to a tech will probably cost you about the same.
good luck,
matt
PS-what are your numbers for deadkey and swing?
(in watts) in AM mode.
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Guardian
Member
Username: Guardian
Post Number: 65
Registered: 5-2004
| | Posted on Thursday, July 19, 2007 - 12:57 am: |
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Where can i send my radio to get it fixed the right way there is no repair shops inspokane any more.Doug |
Guardian
Member
Username: Guardian
Post Number: 66
Registered: 5-2004
| | Posted on Thursday, July 19, 2007 - 7:38 pm: |
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Hey Matt if the mod lmitor was removed in my president grant with the mb8719 pll could that cause it to sound bad if i am tring to use a power mic on it . just was wanting to run that by u or any one else.Thanks Doug |
Dale
Senior Member
Username: Dale
Post Number: 1008
Registered: 12-2002
| | Posted on Thursday, July 19, 2007 - 8:04 pm: |
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well imho that would hurt audio quality in
all modes definately a no no.if your limiter is removed put back in place.theres a vr to adjust
audio.i would also invest in a freq counter
a good one or look around web for radio repair
seems to me that its transmitting off freq.im
no tech but this is just my opions and things ive learned thru the yrs
dale/a.k.a.hotrod
cef426
cvc#64
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