| Author |
Message |
    
Goat373
Intermediate Member
Username: Goat373
Post Number: 134
Registered: 3-2005
| | Posted on Sunday, January 01, 2006 - 5:38 pm: | 
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ok, for some reason my tr-296 wont key up on AM...SSB works fine, but no AM, with 296 on dummy load and another radio on main antenna, i hear faint static with the 296 on AM. SSB to other radio works fine...anyone??. kinda stinks cuz i just got the radio back. |
Patzerozero
Senior Member
Username: Patzerozero
Post Number: 2163
Registered: 7-2004
| | Posted on Sunday, January 01, 2006 - 6:42 pm: |
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is AM receive out too-or only AM xmit? problem with mode selector switch, or connections at switch or board? you hear the 296 on 'other' radio, while keying 296 into dummy load-is power output/wattmeter showing ANY dead key/swing? is AM power and/or AMC turned down too low? or bad VR/connection? |
Goat373
Intermediate Member
Username: Goat373
Post Number: 135
Registered: 3-2005
| | Posted on Monday, January 02, 2006 - 1:06 pm: |
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am resiceve is good. no showing on wattmeter...no modulation, only keys enough to change the tone of the static. no showing on watt meter |
Bc910
Advanced Member
Username: Bc910
Post Number: 658
Registered: 7-2004
| | Posted on Monday, January 02, 2006 - 1:46 pm: |
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I think Pat is right.
Check all the appropriate vrs for propper adjustment and connection, clean selector switch...
BC |
Goat373
Intermediate Member
Username: Goat373
Post Number: 136
Registered: 3-2005
| | Posted on Monday, January 02, 2006 - 10:53 pm: |
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more info...center tap of 1969...SSB 14.14 volts....AM 0.05 volts...hummmmm? |
Goat373
Intermediate Member
Username: Goat373
Post Number: 138
Registered: 3-2005
| | Posted on Monday, January 02, 2006 - 11:37 pm: |
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ok...SSB transmit just went....now im stumps....SSB transmit worked fine...not its out to, down to .5 watts pep...not even that, barely bumps the needle on power scale. |
Goat373
Intermediate Member
Username: Goat373
Post Number: 139
Registered: 3-2005
| | Posted on Monday, January 02, 2006 - 11:58 pm: |
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thinking it may be the final now |
Kid_vicious
Advanced Member
Username: Kid_vicious
Post Number: 975
Registered: 9-2004
| | Posted on Tuesday, January 03, 2006 - 12:00 am: |
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i dont have the voltages handy, but check the voltages on the MB3756 voltage regulator.
also, maybe TR41 needs replacing?
if so, use and NTE152.
TR41 is mounted on the same wall as the MB3756 towards the rear of the chassis.
matt |
Goat373
Intermediate Member
Username: Goat373
Post Number: 140
Registered: 3-2005
| | Posted on Tuesday, January 03, 2006 - 12:28 am: |
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i cant find the voltages ither...anyone have a set...im assuming the specs for the old 4 switch 148gtl's would be the same...also maybe the grant xl's |
Goat373
Intermediate Member
Username: Goat373
Post Number: 141
Registered: 3-2005
| | Posted on Thursday, January 05, 2006 - 8:28 pm: |
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yeah...i think im set on it being the finals now...how can i test to be sure?? |
Kid_vicious
Advanced Member
Username: Kid_vicious
Post Number: 986
Registered: 9-2004
| | Posted on Friday, January 06, 2006 - 12:02 am: |
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get out your DC ammeter and try to bias the driver and final.
the driver bias should be about 30ma.
and the final should be about 60 ma.
if you cant seem to get them set that way; they are probably bad.
matt |
Tech8541
Moderator
Username: Tech8541
Post Number: 257
Registered: 12-2003
| | Posted on Monday, January 16, 2006 - 9:42 pm: |
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i think you have 2 problems. your 1st problem was just that tr41 failed (the am volt.reg/am modulator). hince why you had no am tx but yet ssb was working (am modulator is bypassed and final/driver run directly off 13.8v power source). it is obvious that you have been in the radio because you gave voltage measurements for the final (which also show that the am reg was toast). i think you have now shorted the final and/or driver back their screwing around and blew 1 or both of them also. |
Goat373
Intermediate Member
Username: Goat373
Post Number: 159
Registered: 3-2005
| | Posted on Monday, January 16, 2006 - 10:51 pm: |
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that is very possible...possible indeed...im going to replace then tr41(do you have a part number, i can look at it and read it, but it would be easier if you had it handy) and putting erf-2030's in the driver/final spots, along with there supporting hardware
thanx for the input...much apprieciated |
Tech8541
Moderator
Username: Tech8541
Post Number: 260
Registered: 12-2003
| | Posted on Tuesday, January 17, 2006 - 9:39 am: |
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tr41 is a 2sd1135.
i haven't seen any info released for replacing the 1969 with a erf part in a 148 yet. it may be out, but if not i would not try it. |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1050
Registered: 9-2004
| | Posted on Tuesday, January 17, 2006 - 8:54 pm: |
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the info is here on the forum, just put up recently.
nice to see you back on the forum richard!
do you think the best repalcement for the 2SD1135 is the NTE152 or the NTE291?
matt |
Tech8541
Moderator
Username: Tech8541
Post Number: 261
Registered: 12-2003
| | Posted on Tuesday, January 17, 2006 - 10:46 pm: |
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the best replacement for the 1135 is the 1135. if you can't get it, then go for the nte parts. either will 'get you by'.
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Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1060
Registered: 9-2004
| | Posted on Tuesday, January 17, 2006 - 11:27 pm: |
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thats what i thought. i use the NTE152 and was just wondering if there was an advantage to either.
thanks,
matt |
Goat373
Intermediate Member
Username: Goat373
Post Number: 161
Registered: 3-2005
| | Posted on Wednesday, January 18, 2006 - 12:16 am: |
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well... i just swapped out the driver, final, and tr41...but still no AM power...BUT i found a popped cap in TR41's circuit, so i replaced it and now looking for another 1135...sum monkey
P.S. i did get SSB back
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