President Washington 858, tx problem

redshovelhead77

hi, iam hoping someone can help me out,,,, my p. washington 858 is transmitting at less than 1/2 watt forward power on a telewave meter. it can be heard by another radio on the bench, i bought the radio with this problem,,,,, it was full of dust so i cleaned it up,,,,, after that it briefly transmitted at what seemed to be a normal power level(i didn't have my meter that first day) then it blew the fuse and after replacement it was transmitting weakly,,,,,, so as per the mods page which says c179 can cause no am transmit, dimming of the light, and the fuse to blow, i replaced the cap,,,this did not help at all,,,,,,, i have also cleaned the contacts on the relay,,, it picks and drops well, however it was dirty and had been open before,(super glue) so i cleaned the contacts and tested it with a meter and it seems well,,,, the other thing that may be an unrelated issue/or perhaps is normal,, is that the receive on am is much quieter than on ssb,,,,, it receives on both, however, the am is just much quieter,,,,,, thanks for the help in advance.... mark

Rick · Post by **Rick** » Friday 11th Apr 2008, 10:01

Check the following TR25, TR26, C102, should have about 13 to 13.8 volts at the collector of TR25 and by adjust the pre-set VR6 in AM TX mode, the emitter of TR25 should go from about 4.5 to 8.5 volts. let us know how you get on.

redshovelhead77 · Post by **redshovelhead77** » Sunday 13th Apr 2008, 12:04

Rick thank you for the direction,,, here is what i found,,,C102 checks ok with a fluke meter removed from the board, TR 25 reads when keyed up, collector=13.7,, emitter=7.73,,,,base=8.53,,,,,emitter swings with vr8 from 6.09 to 7.82,,,,,, still i read only .25 watt forward power,, and the radio will still blow fuses on ssb when keyed up for about 2 secs,,,,which i didn't make clear in my first post,,,,am receive still very faint,,,, ssb however is loud,,,,,,,, what should i check next,,,,,also does anyone have a clear schematic for this radio,,,,,,, mark

Rick · Post by **Rick** » Sunday 13th Apr 2008, 19:53

Try un-soldering the collector of the final and driver and check to see if the radio still blows fuse's, if its now ok try replacing the final.

redshovelhead77 · Post by **redshovelhead77** » Monday 14th Apr 2008, 1:51

Rick, i lifted the collecter leg on both the driver and final,,, the fuse no longer blows, so i will order a new final today,, the radio now has a 1306 driver and a 1307 final,,,,, can a replace the 1307 with a 1969 and still use the 1306 driver,, thank you very much for your help,,, mark

Rick · Post by **Rick** » Monday 14th Apr 2008, 3:42

You would be best off with a 2SC2166 driver and 2SC1969 final. They are now getting hard to get hold of has they have not been made for over 5 years now.

Remember to set the bias when you do the job or you may blow the new ones.

redshovelhead77 · Post by **redshovelhead77** » Monday 14th Apr 2008, 5:42

i have found a 1307 as well as a 2166 and 1969, iam not very farmilliar with bias, if i understand the theory, you are setting the voltage so as not to overdrive the transistor, for the sake of keeping things simple, could i use the 1307 as a direct replacement and not have to re set the bias, or is this adjustment required whenever replacing a final,,,,,,

Rick · Post by **Rick** » Monday 14th Apr 2008, 6:45

What ever transistor you use you need to set the bias. No one transistor is the same that why use have bias pre-sets. Look around the net for alignment info it not that to do, you just need a DMV.

redshovelhead77 · Post by **redshovelhead77** » Monday 14th Apr 2008, 9:52

thanks rick, i found the alignment info, and now i can see how to make the adjustment,,,,,not hard at all,,,, iam ordering the parts now, and ill let you know how things turn out after i get them in,,,, mark

Exit_Thirteen · Post by **Exit_Thirteen** » Monday 14th Apr 2008, 10:17

You can do this if your AM Rx is a bit low, adjust VR5 counter-clockwise for more output, also, if you have some patience and a plastic alignemt screwdriver, turn up the volume a bit, or unsolder the speaker, and put a voltmeter on the speaker leads, adjust L3, L4 (dual tuning slug can), L5, L6, L7 for maximum voltage on the voltmeter, or volume on the speaker.

Hope this helps the Rx trouble on AM. Cheers!

-Rick (Triple 7)

Rick · Post by **Rick** » Tuesday 15th Apr 2008, 12:18

Exit_Thirteen wrote:You can do this if your AM Rx is a bit low, adjust VR5 counter-clockwise for more output, also, if you have some patience and a plastic alignemt screwdriver, turn up the volume a bit, or unsolder the speaker, and put a voltmeter on the speaker leads, adjust L3, L4 (dual tuning slug can), L5, L6, L7 for maximum voltage on the voltmeter, or volume on the speaker.

Hope this helps the Rx trouble on AM. Cheers!

-Rick (Triple 7)

What is all the above about? it sounds like hog wash to me, I spend all that money on a sig gen and other test gear.

redshovelhead77

Rick,, iam still waiting on the final and driver,,, but i was looking at the radio tonight, it still has the very faint receive on am,,,,i noticed that when receiving a distant signal, when i turned the noise blocker on the signal went quiet,,,, then i tried it with another radio on the bench,,,, as soon as the noise blocker is on, the receive goes quiet,and the meter to zero, what do you think,, mark

Rick · Post by **Rick** » Thursday 17th Apr 2008, 11:10

The radio would probably benefit from having the alignment done, I know you would most likely not have the test gear to do this, so it would be best to just fit the final and driver, then find a radio tech in you area to do a full alignment job.

There maybe an underling faults with the RX strip but with out doing the alignment you will never know, and could waste a lot of time trying to find a fault, which is not there.

All radios, which come in to me for repair, have the alignment done as part of the job, this is the only way to make sure it is right when it go out of the workshop.

redshovelhead77

rick,,,, thank you,,, i was thinking to have a full alignment done,,,, so it shall be,,,,,ill keep you informed,,, mark

redshovelhead77

Rick, i have installed the new driver and final, the old final was shorted out badly, the job went well except that i still do not transmit, i also could not get the bias set down as low as called for, iam wondering if the shorted final may have blown another component? tomorrow i plan to reinstall the old driver, at least with it it put out a bit,,,, iam wondering if i possibly could have received a bad driver,,,

redshovelhead77 · Post by **redshovelhead77** » Sunday 20th Apr 2008, 8:03

upon further examination the radio does put out a bit but its very weak cannot be measured with a meter,,,,,, this makes me think the shorted final damaged something near it perhaps a cap,,,,,,let me know if you have any ideas, or if you need readings,,,,, mark

redshovelhead77 · Post by **redshovelhead77** » Sunday 20th Apr 2008, 8:42

driver b=.66 c=13 e=0 final b=.586 c=13.3 e=0

Rick · Post by **Rick** » Sunday 20th Apr 2008, 9:59

You have a PM.

redshovelhead77 · Post by **redshovelhead77** » Sunday 20th Apr 2008, 11:36

wankle · Post by **wankle** » Monday 29th Sep 2008, 12:41

Did you ever get the radio fixed. I have one doing the exact same thing.
I replaced the finals. The voltages are correct.
any help would be appreciated.
It has about .5 watt output.
thanks

skybolt58 · Post by **skybolt58** » Friday 14th Nov 2008, 20:13

I am not having a problem with transmit, but my rec is weak, and I cant find L7.. I have the 858 version, also. I cant run a silver eagle or a galaxy echo mic on it, bad squeal when turned up any?

ANy Ideas?

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