trying to ad talkback (resistor across p.a) to a grant by president...anyone know how i can put talkback on this radio? thanks for any help
-
You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
president grant
- Thread starter johnecashflo
- Start date
then its basically the same as doing it on a 29LTD as shown here:
Adding talkback to your radio - and easy modification for beginners
of course the boards dont look exactly alike, but you will find two solder pads right at the back edge of the radio, and you will see that they are right underneath the EXT and PA speaker jacks.
these are the two pads to add the 100 (or so) ohm resistor between.
or put it on a SPST switch to make it switchable.
LC
Adding talkback to your radio - and easy modification for beginners
of course the boards dont look exactly alike, but you will find two solder pads right at the back edge of the radio, and you will see that they are right underneath the EXT and PA speaker jacks.
these are the two pads to add the 100 (or so) ohm resistor between.
or put it on a SPST switch to make it switchable.
LC
thanks for the great post.. im familiar with this mod..it was the first one i tried,it didnt work.. the pa switch is on the squelch knob..you turn the squelch knob till it clicks off, which in turn shuts the transmit on the radio down and turns on the pa.. ran jumper from pa switch to ext speaker on solder side of board ..it gave me audio (talkback)but no carrier or modulation..it seems like anytime you make the pa hot it kills the radio (transmit )
sorry about that.
i have a schem for the madison, so ill try to come up with something.
i will post back if i do.
LC
i have a schem for the madison, so ill try to come up with something.
i will post back if i do.
LC
thanks for the help L.C. im just a doit yourself guy trying to update this radio for a guy at work..
I had a Pres Grant awhile back. I know on alot of exports it won't work crossing the pa terminal. Not sure if the Grant is included it that same senaro???
good point oldtimer, if his Grant is the export model, then its going to be different than the 148 style chassis.
johnecashflo,
i cant seem to find any differences between the grant and the 148 with regards to how the PA and EXT SPEAKER jacks are wired.
my guess is that you were trying the wrong two solder pads.
what you want to do is connect the outer shell (ground) of the EXT SP. jack to the outer shell of the PA SP. jack through a resistor.
to find the right solder pad, put your voltmeter on continuity mode, and put one lead right inside the hole of the EXT SP. jack and touch it to the side of the jack.
then put the other meter lead on the solder pad you think it is and make sure there is continuity between them.
do the same with the PA SP. jack and you should have the right pads.
they should be the solder pads closest to the back of the radio right underneath the jacks.
remember that you are connecting the "grounds/shields" of the jacks, not the center pins.
from what i can tell, this should work.
LC
johnecashflo,
i cant seem to find any differences between the grant and the 148 with regards to how the PA and EXT SPEAKER jacks are wired.
my guess is that you were trying the wrong two solder pads.
what you want to do is connect the outer shell (ground) of the EXT SP. jack to the outer shell of the PA SP. jack through a resistor.
to find the right solder pad, put your voltmeter on continuity mode, and put one lead right inside the hole of the EXT SP. jack and touch it to the side of the jack.
then put the other meter lead on the solder pad you think it is and make sure there is continuity between them.
do the same with the PA SP. jack and you should have the right pads.
they should be the solder pads closest to the back of the radio right underneath the jacks.
remember that you are connecting the "grounds/shields" of the jacks, not the center pins.
from what i can tell, this should work.
LC
- No one is chatting at the moment.
