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Rodder54
Junior Member
Username: Rodder54

Post Number: 29
Registered: 12-2001
Posted on Friday, April 05, 2013 - 7:06 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i have a president washington , the mod on it sounds loud on a dummy load, with a radio in same room , but on any meter it only does about a half watt i had this same thing wrong with a 2950 once but i can not remember what was the cause.if you have any suggestions, on know any place to send off to be fixed it would be great i dont mind buying some parts a changing them to try it my self thank you
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Tech237
Moderator
Username: Tech237

Post Number: 1669
Registered: 4-2004


Posted on Saturday, April 06, 2013 - 8:54 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Check the finals and associated parts. it's possible you are transmitting on the pre-finals or drivers only.

Testing with another radio in the same room, is never really a good test even when running into a dummy load. I have known name brand dummy loads that would radiate a signal for 5 miles, albeit well attenuated. In fact I used to use one on a hidden transmitter.
Tech237
N7AUS

God made me an athiest, who are you to question his wisdom?
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Rodder54
Junior Member
Username: Rodder54

Post Number: 30
Registered: 12-2001
Posted on Saturday, April 06, 2013 - 4:46 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i just used a old pro510 to see if i had audio, it has a driver transistor c2166 and final c 1969 are those what you think i should change thanks
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Tech237
Moderator
Username: Tech237

Post Number: 1670
Registered: 4-2004


Posted on Sunday, April 07, 2013 - 9:05 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

the Final transistor maybe worth replacing. If you getting 500mW out, I expect the driver is OK.
Tech237
N7AUS

God made me an athiest, who are you to question his wisdom?
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Rippedradio
Intermediate Member
Username: Rippedradio

Post Number: 137
Registered: 7-2002
Posted on Sunday, April 07, 2013 - 11:04 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I had a 148GTL That was doing a half a watt. thought it was the final but ended up being the driver. Final was O.K. Changed the driver and bam back to normal! I thought without the driver the final could not work but they do this radio stumped me for awhile!
You Gotta Pay to Play!
RCI2970
SS158EDX
SS3900GHP
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Rodder54
Junior Member
Username: Rodder54

Post Number: 31
Registered: 12-2001
Posted on Monday, April 08, 2013 - 11:06 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

thanks ill replace both and try that thanks for the help.
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Rodder54
Junior Member
Username: Rodder54

Post Number: 32
Registered: 12-2001
Posted on Thursday, April 18, 2013 - 8:59 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

hi, i replaced both. the final is the one that gave me swing but on am only. no ssb and just enough carrier to get a reading on the frequency counter. any ideas thank you guys for the help.
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Rodder54
Junior Member
Username: Rodder54

Post Number: 33
Registered: 12-2001
Posted on Friday, April 19, 2013 - 11:23 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

some one said it might be the D717 transistor is that some thing that i might try?
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Rodder54
Junior Member
Username: Rodder54

Post Number: 34
Registered: 12-2001
Posted on Monday, April 29, 2013 - 8:10 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

any one know what else i can change and try, thanks
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Tech237
Moderator
Username: Tech237

Post Number: 1673
Registered: 4-2004


Posted on Saturday, May 04, 2013 - 9:13 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Check caps and resistors for faulty ones
Tech237
N7AUS

God made me an athiest, who are you to question his wisdom?
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Rodder54
Junior Member
Username: Rodder54

Post Number: 35
Registered: 12-2001
Posted on Monday, May 06, 2013 - 10:46 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

thanks ill check as i can is the D717 a voltage regulator i was told it might need to be replaced not enough power i cant buy one if i dont know for sure what it is ,thanks
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Tech237
Moderator
Username: Tech237

Post Number: 1674
Registered: 4-2004


Posted on Tuesday, May 07, 2013 - 8:54 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I'll check my files (now they are all unpakced and filed again) I may have a diagram and some more information. Will look tomorrow on my day off.
Tech237
N7AUS

God made me an athiest, who are you to question his wisdom?
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Rodder54
Junior Member
Username: Rodder54

Post Number: 38
Registered: 12-2001
Posted on Wednesday, May 22, 2013 - 10:36 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i checked the caps and resistors best i could it swings to 5 or 6 watts on am dead on ssb and about 1/2 watt dead key on am any thing else i can try or send off,?
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Sonoma
Intermediate Member
Username: Sonoma

Post Number: 266
Registered: 11-2001


Posted on Thursday, May 23, 2013 - 7:14 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

is this the 858 PLL or the 8719 PLL. this radio is old and is bad about the 10 volt caps going bad. it will cause problems you have. they will look good but dry out and kill a lot of the radio voltages.
if it is the 858 PLL there is some other items that can cause this also.
check the bias voltages and see if they will adjust. the vr's can go bad on the old radios. I just refurbished 3 last July that are my radio's and they had some of the same symptoms.
C179 on the 858PLL goes bad and kills power out on ssb. it is a blue tantulum 2.2uf cap by the bias vr's you can put a 2.2 electro cap 25 volt in place of it. I can rattle on for hours on this radio so let use know what you cab test.
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Rodder54
Junior Member
Username: Rodder54

Post Number: 39
Registered: 12-2001
Posted on Friday, May 24, 2013 - 12:35 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

its the 8719 what should i check on this one thanks

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