I thought I'd post up a few extra details on the ERF-2030 mod for the Cobra 25/Uniden 66/68 since I haven't seen them floating around anywhere.
First, follow the instructions on CBTricks here: http://www.cbtricks.com/miscellaneou...bra_25_mod.pdf
Instead of removing R38 replace it with a 10K 1 watt. You can use higher values like 15K+ if you want.
If you don't want to make this mod reversable, instead of just removing he tuning slug from L10, take a turn off the coil and keep the slug to fine tune the output. Remember, you have to scrape the coating away from the coil wire to resolder.
If you're planning on using this radio with a linear that needs a low output, you will now have about a 2 watt carrier with about 40+ watts peak output.
Personally, I don't like the way a radio sounds with that little amount of carrier to peak ratio, so I like to bring up the carrier. Here's how you do it on this radio:
-Change C46 to a 390pf cap
-On the solder side of the board, run a small wire from the positive side of C114 with a 4.7K resistor inline toward the gate of the ERF2030. If you're looking at the face of the ERF2030, it's the left leg.
Now do a TX
align on the radio.
This will bring the carrier up to about 5-6 watts. Total peak output will be usually be around 40-45 watts.
Personally, I still prefer doing these radios with the 2SC1969 final and 2SC2314 driver. It yields a little more power and I like the way it sounds a little better. You can combine parts of the two mods together if you want.
I think the 25LTDs are great little AM
radios. They're a really good size for a mobile, are capable of a lot of power and you can use all the mods on them that are available on the larger 29 chassis if you're willing to take the time to cross reference the schematic.