You Wrote:
"I have sound and rx now...found a bad solder joint from IC107 to the board......
still have no transmit, nothing on the meter, sound does mute when i key..have power from Q125, nothing to IC106, R172-R173-R174 according to the schematic..but the block chart shows something different
this is my first radio project and probably my last for a while(lol)
what should i check next, the problem is a little different now ...any ideas???
thanks again
buddygunzz "
======================
Hi,
Did you say if the TX indicator comes on when you key?
Lets see if I can help,
I have posted the Voltage charts for IC's and Transistors on my website.
Rogerbird.tripod.com
** NOTE: I corrected the Charts today- 2/3/04 - I noticed a Major Mistake - swapped Collector and Base.. Sorry...
Ok, Here goes:
I know you said your getting voltage from Q125..It should be:
Q125 the TX Switch transistor..
TX Emitter Should be: 7.3v
Collector Should be: 7.8v
Base Should be: 8.0v
RX Emitter Should be: 7.3v
Collector Should be: 0.0v
Base Should be: 8.0v
Now if thats good, You should check the Tx Chain,
Check the collectors of Q124, Q133,& Q132.
Q124 C= 7.8v in TX
Q133 C=12.3v in TX
Q132 C= 11.5v in TX
Voltages are approx.
If those seem correct, check to see if the Bias current is good,
Remove the B002(PB-100) from the Main PCB.
Connect a DC Ammeter (+) to TP4, (-) to TP3.
Adjust VR112 for 50mA reading on the DC Ammeter.
Connect a DC Ammeter (+) to TP4, (-) to TP2.
Adjust VR113 for 50 mA reading on DC Ammeter.
If those are way off or not adjustable you may have damaged Bias Diodes or Finals.
Lets see what that gives us..
Roger
</p>Edited by: <A HREF=http://pub86.ezboard.com/bworldwidecbradioclub.showUserPublicProfile?gid=rogerbird1>Rogerbird1</A> at: 2/4/04 2:14 am
"I have sound and rx now...found a bad solder joint from IC107 to the board......
still have no transmit, nothing on the meter, sound does mute when i key..have power from Q125, nothing to IC106, R172-R173-R174 according to the schematic..but the block chart shows something different
this is my first radio project and probably my last for a while(lol)
what should i check next, the problem is a little different now ...any ideas???
thanks again
buddygunzz "
======================
Hi,
Did you say if the TX indicator comes on when you key?
Lets see if I can help,
I have posted the Voltage charts for IC's and Transistors on my website.
Rogerbird.tripod.com
** NOTE: I corrected the Charts today- 2/3/04 - I noticed a Major Mistake - swapped Collector and Base.. Sorry...
Ok, Here goes:
I know you said your getting voltage from Q125..It should be:
Q125 the TX Switch transistor..
TX Emitter Should be: 7.3v
Collector Should be: 7.8v
Base Should be: 8.0v
RX Emitter Should be: 7.3v
Collector Should be: 0.0v
Base Should be: 8.0v
Now if thats good, You should check the Tx Chain,
Check the collectors of Q124, Q133,& Q132.
Q124 C= 7.8v in TX
Q133 C=12.3v in TX
Q132 C= 11.5v in TX
Voltages are approx.
If those seem correct, check to see if the Bias current is good,
Remove the B002(PB-100) from the Main PCB.
Connect a DC Ammeter (+) to TP4, (-) to TP3.
Adjust VR112 for 50mA reading on the DC Ammeter.
Connect a DC Ammeter (+) to TP4, (-) to TP2.
Adjust VR113 for 50 mA reading on DC Ammeter.
If those are way off or not adjustable you may have damaged Bias Diodes or Finals.
Lets see what that gives us..
Roger
</p>Edited by: <A HREF=http://pub86.ezboard.com/bworldwidecbradioclub.showUserPublicProfile?gid=rogerbird1>Rogerbird1</A> at: 2/4/04 2:14 am