I have a Uniden PC122XL that I am experimenting with.

I actually did the "Handy Andy" mods to the power section of it for starters ( PC-122 Power Mods and miscelaneous stuff... )...

But I want to make this thing louder. I am also planning to see how wide I can get the audio bandwidth... Just because.

Does anyone know the NPC-RC mod for this radio?

Check this page...lots of info for that radio:

PC-122 Power Mods and miscelaneous stuff...

The 122xl and Grant xl are nice radio's for what they are and do. You will never make one talk on AM like a Stryker though. I would try to make it be all it can and then leave well enough alone.

PC-122s are loud from the get go . You want louder ? Use a D-104 hand held. When someone says they want a louder PC-122 , I'd think you had a lemon or something. Good luck.

Thanks for the replies gents,

Thanks Moleculo, those are the "handy Andy" mods I mentioned. I've completed those.

Switch:

it isn't just about "Louder Audio", it is about more audio with quality audio. Like 150% positive modulation and limited to 99% Negative modulation.

I bet that looks great on a scope, That guy 10 channels away can hear you too.

I didn't catch that one. No such thing as 150% audio . It's either 100% scoped out or over the hills and far away. That's all good with me. NPC / Swing / Diode / jump'in this and that and it all adds up to the same thing.

I said the PC-122s were pretty darn good loud radio out of the box with a slight tune , I have nothing against all the wham whams and zoo zoo's a guy can do to his radio to make it do this or that. To each his own.
There's a lot of radio there in a small chassie. Although they are no 148/Grant , they can hold there own for what they are.

PC-122s are decent small chassied AM/SSB'er's . Experiance has taught me (especially on these radios) to much is to much. They will run hot and eventually fail when they didn't need to. Those radios set at 100% are LOUD ! Run a box ? 2 to 8 would get job done nice at the 100% , they will do 20 on SSB ,but running a box ? one might drop the carrier down a little for a cooler running radio in the long and short of it.

Your NPC type mod will work as far as running the box goes on AM , but the audio chip and voltage regulator on those radio run side by side and they will get hot to the point of burning you and up , those audio chips ain't cheap either (if you can find them) like I said before , best to take it easy on those radios , there decent and will stay that way while being treated nicely.

Not true.

Overmodulation on the Negative causes the splatter.

AM broadcast stations can legally run up to 125% positive and 100% Negative modulation.

If you overmodulate in the negative direction, you splatter... if you can keep the negative at 100% of slightly less, you can run more positive modulation, hence louder, clean audio.

The reason I am using a PC122XL is because I have one here... and I don't use it

Also, the PC122XL doesn't use a modulation transformer, so I can run more audio bandwidth without the transformer limiting it