NEW COBRA 29er LX with ELEFLOW 1969 version

[PLUMMER]

I wanted to throw out a few questions for the guru's and experts on this conversion.

Eleflow HFR-20w replacement for the Mitsubishi 1969 from weasel66 in England
The LX came with the 2sc2314 driver and I had an older one from a Uniden
The older Uniden seems to put out more power, just for notation
C42 > NTE 3300uF 16v Electrolytic Capacitor
Installed a KEM 104 potentiometer instead of the 1K-1w-resistor
D11 > add (in series) an NTE 1k-1w-resistor 2% w/wire protection
R48 > NTE 33k-1w-2% Resistor, w/wire protectors
R55 > NTE 10-1w-2% Resistor w/wire protectors and an NTE 47ohm 1kv cap in parallel across R55 on pcb side
C37 & C68 > NTE .22uF 100v monolithic Dipped Capacitors
JP36 > NTE 220uF 35v Electrolytic Capacitor in series with an NTE 33-150ohm-1/2w-2% Resistor to achieve 4:1 ratio dead key to peak.
Also trying with the jumper back in or stock.
Adding a 68pf cap across C59 , also tried 100pf cap. still testing this....
Ceramic Capacitor #104k or 100,000pF 50v cap ( or a 103) at TR12 on the middle prong and then the prong closest to the tuning knobs of the same TR12 component. This changes the squelch break and eliminated alot of the annoying static.
C71 > 220uF 35v electrolytic cap
I have not done the D8 jumper yet, as I have not found a description of what it does. Nor changing R58 to a 4.7 ohm ?


On the tuning coil I have some questions, counting the coils exactly. The directions to this mod call for cutting of the 5th coil or turn off of L14. Well mine has 4.5 turns exactly like the fixed L16. I've tried just removing the slug, big power gain, then I tried an identical coil but with 3.5 turn from the old uniden with the slug in. Slightly less power maybe 2 watts cold and almost unnoticeable when it warms up ???? I then also added the 68pF cap to one leg however I don't know if its supposed to be the leg on the antenna side or the JP36 side.It says to ground, I assume this means to the chassis or metal frame and not the negative side of the pcb like one of the philips screws? Either way there wasn't any noticable difference in sound while talking 6.2 miles with a base on level ground in the suburbs.
Coils L13 & L12 both have exactly 7.5 turns and have been split or spread exactly in the middle of them. It appears as if someone used a #2 sharpened pencil and just made a nice V. The rest is tight as it came from the factory. Will touching these coils ruin sound quality? I've seen pictures of L12 completely stretched like a loose old telephone cord...... How much do you gain in power from tweakn' them? I have extras from the Uniden to test, but I don't wanna mess with the Originals. Its going in tomorrow if there is time to squeeze in for a tune. Thanks

 

[PLUMMER]

Does anyone know what the difference would be for the C71 change. Stock it's a 10v 220uf cap, but the mod calls for a 33uf and doesn't mention voltage. A random poster mentioned 35v. From everything I understand it really doesn't make a difference as long as you don't use a smaller E cap. Can anyone tell me what this actually does.

Also R58 has a 8.2 ohm resistor 1/4w, it calls for a 4.7ohm, this looks like it adds more power to L16, thus also requires adding 68pf to C62.

Another thing I noticed was R52 has a 102 pot instead of a resistor like the lx pcb schematic shows, probably no big deal, but what does this effect.

Thanks