10 turn pot clarifier mod

[BOOTY MONSTER]

a thread pops up once every bluemoon that mentions clarifier pots that turn multiple times or are gear driven to reduce the pots actual travel . these seem to be a good idea . i was wondering what others thought of them , and if they are a good thing what specs do i need to look for to replace the clarifiers in my washington and grant XL with them . or a link to the proper pot would be nice too .

 

[555]

I have a 10 turn Variable Power installed on my cobra 29
very nice and stable the other varaible were kinda turn it just a tad and wham its to much then get it sit then have to come back later and reset it
10 turn stays on but this is on my rf power control

 

[packrat]

I have a 10 turn clarifier pot in my 2000 and it works quite well. It was there when I bought the radio, so I dont know what the mod number is.

Sorry.

PR

 

[Robb]

I'm pretty sure that I'd seen the 10-turn clarifier on CBTricks in their "Secret CB Files". It might takes some digging to find, but...

This isn't for a 10-turn clarifier; but just for extra slide on the 148.
I think it requires a 'super diode' to make the the 10-turn work correctly.

COBRA 148 GTL SLIDE
1. --- Remove R-44, R-175 & D-52.
2. --- Install jumper where you removed R-175.
3. --- Move orange wire on Clarifier to Pin 1 of IC-4
4. --- Jump R-174 or clarifier WILL NOT center up.
NOTE : L-23 (AM), L-59 (USB), L-22 (LSB), will have to be readjusted for center slot on Clarifier control - some units slide more than others.

NOTE ALSO: if you change D-35 to a ECG-612, the stock clarifier will be sensitive and hard to control so, you will have to change VR-502 to a 10 turn pot.

After doing this you MUST re-tune L-23, L-59 and L-22. See my tune-up section {above} on the Cobra 148 GTL.

It would be a good idea to let the radio settle out for a few days in the ON position then re-tune it again.
"WANT MORE SLIDE?"
"1. Remove D51 and put in a jumper."
"2. Install a "super-diode" in place of the stock varactor D35."
"3. Or, add a 4.7uh to 10uh choke to the banded-end of the stock varactor."

SLIDE AND ALIGNMENT FOR THE 148GTL MY WAY

 

[MisterFatty]

nothing Super needed to use the 10 turn Pot.... After all your just replacing the standard pot....

The expanded range Varactor (Super Diode) is just going to expand the tunable range. truthfully the only time I've considered the 10 turn useful is on the old shool 23 channel radios that often went 4 or 5 channels on the standard clarifier control, and then all those turns were more annoying then anything...

Whats the sense of a 10kc+ range on the clarifier? Do it right, use the PLL, after that about 6 is perfect, gets you anywhere, not to sensitive, and don't have to turn a stupid knob 5+ revolutions to tune someone in...

I guess it ends up being preference, but even the Old days of 40+kc on a clarifier control never seemed to be an issue..

The real challenge will be locating the proper 10 turn pot, never was a reliable supply for them from anyone I ever bought from, places like H&Y, or Selman had them occasionally but they were always hugely overpriced....

Radios I've had with them always ended going back to single turn, and tossing the 10 turn annoyance in a box...

If you do source one, probably $20+ dollars, maybe someone here will have something in a junk box...

If you want to trick out those radios, Put "The Mod" in them, give the clarifier about 6kc range, and you'll have a nice radio.... You don't even need to be to terribly technically inclined to install, the process is actually pretty "FOOL-proof"

And if all thats not enough, those big ass knobs they use look retarded.....

 

[loosecannon]

i like a 10 turn pot for the base station because when you are DXing, you need to make small adjustments all the time for different stations to account for them being off freq just a bit.
the 10 turn allows me to tune in voices much easier than the stock pot does, as the adjustment can be so small that it gets annoying to try to move that little of an amount.

in a mobile station, i dont like them.

i suppose if i ever found one that didnt turn so easily, i wouldnt mind using one, but while driving, they can be cumbersome simply because of how easily they turn.

im not a fan of big slide in a radio, but i do like to be able to move at least 6khz in each direction so i can work the even freqs.

the value you want for the washington and the grant XL is 20K ohms.

NTE makes one, and you can also find them at mouser electronics.

they are not cheap, and will run 10 bucks or more.
LC

 

[Wrench]

My old, burnt up in a fire, 2000 had a 10 turn. With the Super Diode and 5.7 choke, it seemed like i needed a 20 turn. The radios were busy in DC, so there was a lot of between channel talk going on. Mine had a locking device on it. They are still available online, if you search "vernier pot control knobs."

 

[Klondike Mike]

The definitive answer on this topic lies in thread I started on CBTricks a couple years back for a Cobra 2000. The executive summary is that I got a couple of 10-turns from an eBay source in China for half the price here in North America and NOT to use any "super diode". Thanks again always goes out to LC for the one "super tech" on solving my problem at the time. See complete thread below, be forewarned though, its a lengthy but worthwhile read;

CBTricks Link

 

[ddbddg1]

i dunno about 10 turn pots and stuff but i know the clarifier in mine was too touchy so i just put the biggest knob that would fit on there and it works.
its not touchy anymore