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Message |
    
Semi
New member
Username: Semi
Post Number: 1
Registered: 7-2005
| | Posted on Friday, July 08, 2005 - 9:56 am: | 
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Hello everyone. New here and need some help.
I have an older 148gtl and power seemed to be dropping on ssb after talking for a while.
Felt around and the driver was getting hot (1306). Replaced it with 2166 and power dropped about 8-10w ssb 4-5w am. How do I get more drive to 2166? New driver is good and installed right.
Any help is appreciated!
Thanks
semi |
Bulldog369
Intermediate Member
Username: Bulldog369
Post Number: 266
Registered: 2-2004
| | Posted on Friday, July 08, 2005 - 1:10 pm: |
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turn the driver bias pot up |
Semi
New member
Username: Semi
Post Number: 2
Registered: 7-2005
| | Posted on Friday, July 08, 2005 - 2:02 pm: |
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Bulldog
Thanks for the reply. I set the bias when I installed it. It does hold it's power now but out put is just less.
Could the driver be volted like the final or am I smokin somethin?
semi |
Twowatt
Junior Member
Username: Twowatt
Post Number: 27
Registered: 7-2005
| | Posted on Friday, July 15, 2005 - 12:18 am: |
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semi,
the average 2166 has less gain (beta or hfe) than the avg 1306, and therefore less output.
[when changing transistors, beta is VERY VERY important - rec, xmit, modj, etc]
i think u have 2 options: (1st) get several 2166's and using a digital hfe meter, check each one and install the one w/the highest hfe. (2nd) get a new 1306 and make sure is has the right amount of heat sink compound on it, and mount it snugly and correctly, (using an aluminum oxide insulator preferably), and adj the bias correctly, and it should not get hot.
(i can't tell u the 100's of "good" 1306's i've used over the past 30+ years without a heating problem)
regarding the volted driver, in my mind {some would say i live in my own little world, but it's o.k....they know me here.}, i do see a way that it MIGHT work, (this would involve volting both the final and driver), but my instinct says to only volt the final. (i'm not sure how volting both, **with the other modification needed for am**, would affect ssb).
hope this helps |
Semi
New member
Username: Semi
Post Number: 3
Registered: 7-2005
| | Posted on Saturday, July 16, 2005 - 12:27 am: |
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Thanks Two Watt
Is it still possible to get 1306's?
RF parts says to use 2166 instead and I've been through that. Went back and changed some electrolytics in that area and retried the 1306 and seems fine now.
But if I could find some 1306 I would buy them.
I appreciate the explanation, it's been very helpful.
Take care
Semi
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Twowatt
Junior Member
Username: Twowatt
Post Number: 30
Registered: 7-2005
| | Posted on Saturday, July 16, 2005 - 12:30 pm: |
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hey semi,
do a google search, you'll find them
regards
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