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Hello everyone, I have a 142GTL with a 2SC2078 rf final installed as a driver!

I have a 2SC2166 And would prefer to return the radio back to original spec.
Here is the 100 Ohm Bias Resistor, And the Trace goes to pin1 of the 2166 (base), to junction of c215 i think.
[photo="medium"]4231[/photo] .
Measured:
[photo="medium"]4232[/photo] .
The numbers did not come out in the photo, but it is a 2SC2078 installed as a driver "pushing along" a 2SC1969.

And the RF Final could be a fake, as the radio only does 2-3 watts @ 95% mod!
[photo="medium"]4233[/photo] .

& Yes the radio is ready for a cleaning & a re-cap, I know lol.

To install a proper 2SC2166 driver in this rig, pull the 100 Ohm resistor, & set the bias to FSM specs.?

I need a little help/advice on things to look for that may have been changed.
What key components may be modified from original value in regards to the bias on this radio.

I do not have a Sam's Photofact on this one, perhaps a FSM for the Uniden PC-385 series boards exists online?

I am absolutely lost on how to set the bias! I've never done that before!

Also I found 50mA and 100mA online but I'm not certain which for which i.e. 50mA for the driver or for the final? !

Has anyone seen this mod, and know what to check to revert back to stock?

I here the 2078 has more gain than the 2166 (haven't read the datasheets in a bit), I just want a factory radio now, with no-wack-pack mods..

Best Regards
-Leap

Here is a snap of the schematic:
[photo="medium"]4234[/photo]

<blockquote data-quote="LeapFrog" data-source="post: 566038" data-attributes="member: 46697">Hello everyone, I have a 142GTL with a 2SC2078 rf final installed as a driver!I have a 2SC2166 And would prefer to return the radio back to original spec.Here is the 100 Ohm Bias Resistor, And the Trace goes to pin1 of the 2166 (base), to junction of c215 i think.[photo=&quot;medium&quot;]4231[/photo] .&nbsp;&nbsp; Measured:[photo=&quot;medium&quot;]4232[/photo] .The numbers did not come out in the photo, but it is a 2SC2078 installed as a driver &quot;pushing along&quot; a 2SC1969.And the RF Final could be a fake, as the radio only does 2-3 watts @ 95% mod![photo=&quot;medium&quot;]4233[/photo] .&amp; Yes the radio is ready for a cleaning &amp; a re-cap, I know lol.To install a proper 2SC2166 driver in this rig, pull the 100 Ohm resistor, &amp; set the bias to FSM specs.?I need a little help/advice on things to look for that may have been changed.What key components may be modified from original value in regards to the bias on this radio.I do not have a Sam&#039;s Photofact on this one, perhaps a FSM for the Uniden PC-385 series boards exists online?I am absolutely lost on how to set the bias! I&#039;ve never done that before!Also I found 50mA and 100mA online but I&#039;m not certain which for which i.e. 50mA for the driver or for the final?&nbsp; !Has anyone seen this mod, and know what to check to revert back to stock?I here the 2078 has more gain than the 2166 (haven&#039;t read the datasheets in a bit), I just want a factory radio now, with no-wack-pack mods..Best Regards-LeapHere is a snap of the schematic:[photo=&quot;medium&quot;]4234[/photo]</blockquote>

[QUOTE="LeapFrog, post: 566038, member: 46697"] Hello everyone, I have a 142GTL with a 2SC2078 rf final installed as a driver! I have a 2SC2166 And would prefer to return the radio back to original spec. Here is the 100 Ohm Bias Resistor, And the Trace goes to pin1 of the 2166 (base), to junction of c215 i think. [photo="medium"]4231[/photo] . Measured: [photo="medium"]4232[/photo] . The numbers did not come out in the photo, but it is a 2SC2078 installed as a driver "pushing along" a 2SC1969. And the RF Final could be a fake, as the radio only does 2-3 watts @ 95% mod! [photo="medium"]4233[/photo] . & Yes the radio is ready for a cleaning & a re-cap, I know lol. To install a proper 2SC2166 driver in this rig, pull the 100 Ohm resistor, & set the bias to FSM specs.? I need a little help/advice on things to look for that may have been changed. What key components may be modified from original value in regards to the bias on this radio. I do not have a Sam's Photofact on this one, perhaps a FSM for the Uniden PC-385 series boards exists online? [I]I am absolutely lost on how to set the bias! I've never done that before! Also [/I]I found 50mA and 100mA online but I'm not certain which for which i.e. 50mA for the driver[I] or for the final? [/I]! Has anyone seen this mod, and know what to check to revert back to stock? I here the 2078 has more gain than the 2166 (haven't read the datasheets in a bit), I just want a factory radio now, with no-wack-pack mods.. Best Regards -Leap Here is a snap of the schematic: [photo="medium"]4234[/photo] [/QUOTE]

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