| Author |
Message |
    
Snowman709
| | Posted on Tuesday, October 21, 2003 - 10:23 pm: | 
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it is like the recieve is being over driven and it wont turn very loud but it sounds like it is but after it gets so high on the knob it starts squeal through the speaker |
Kc0gxz
| | Posted on Wednesday, October 22, 2003 - 3:40 pm: |
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Snowman709
What modifications have been done to this radio?
Jeff, kc0gxz. |
Ss8541
| | Posted on Monday, October 27, 2003 - 9:44 pm: |
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sounds like the 'spike' diode has been jumpered. this will give a slightly higher output in tx but will make the rx audio distort after the knob has been turned past a certain level.
the 'techs' that offer this mod or suggests it do not realize that the diode is there to protect the final and driver from spikes from the transformer when the ptt is released. they also do not realize or do not care that it distorts rx audio.
i can't remember the board # for that diode, but it is very close to the audio transformer. |
Kc0gxz
| | Posted on Monday, October 27, 2003 - 11:10 pm: |
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Ss8541
Are you refering to what THEY (whoever THEY are) call the D-9 audio limiter?
I've seen these radios squeal when the receiver volume is turned up too far after D-9 has been cut. I wondered if we were thinking of the same thing.
Jeff. |
Ss8541
| | Posted on Tuesday, October 28, 2003 - 9:09 pm: |
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jeff,
i think we are in the same book, but not on the same page. i am -not- refering to the audio limiter/amc. the diode i am talking about is a diode that is in series with the dc power bus/modulation bus from the aduio transformer. many 'techs' will jump this diode because it gives a few more watts due to the slight increase in voltage.
i looked at the schem for the 25 while i was at the shop today, and i think that the diode that i am talking about for 25 is d8. if i get time tomorrow, i'll recheck it and post from there. |
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