Jay,

You might want to id which of the three production runs/models you have in case this board is one of the "variables".

73,

Evan, K9SQG

On Friday, December 20, 2024 at 02:48:04 PM EST, Jay W6CJ via <lastradioman=[email protected]> wrote:

Looking for a PC board foil diagram that shows the connections to, and around the R55 bias pot.??

Thanks & 73

Jay

W6CJ

Jay:

What is the serial number of your R-4C?? There are some very special "gotcha's" to pay attention to on the late "metal-geared" PTO (and as Steve said it still has two plastic gears in it) should you be pulling it apart for cleaning.

May be slow to answer today...away from the computer/internet for much of the day.

73

Peter

VE7PS

On Thu, Dec 19, 2024 at 4:12?AM Steve Wedge, W1ES/4 via groups.io <w1es=[email protected]> wrote:

I agree with everything Peter has listed except that I use mineral spirits for the ball bearings and their race.?

I will add that you won’t get the PTO to be as light and smooth as the earlier designs but you can come close — especially with the “metal gears” version (there are still one or two nylon gears in a “metal gears” PTO).?

Be very careful to put any nylon washers back where they originally were. The locations and thicknesses of these washers can vary — they were used to fine-tune the geartrain.?

73,

Steve Wedge, W1ES

Time flies like an arrow. Fruit flies like a banana.

Sent from for iOS

On Wed, Dec 18, 2024 at 23:10, VE7PS via groups.io <ve7ps@...> wrote:

Jay;

There are many reasons that can contribute to "grabbing" or "sticky" tuning on the C-line dials.? Often there can be more than one reason.? Full teardown is always my choice but I understand that can be?a daunting task to face for the 1st time.??

Before doing that I would recommend?reading and studying two articles. Both are on WB4HFN's website.

The first is by Neil, K1VY;

The 2nd is by me, and can be found here;

It starts on Page 15.

If pulling the PTO seems a bit much, you could try cleaning out the front bearing with long Q-tips and rubbing alcohol.? You will need at least a half?dozen swabs to get it clean.? Once clean, re-lube with a light grease.? I prefer copper infused moly grease these days, but have used white lithium in the past.? Both work well for me.? Unfortunately?one often finds burrs on the 1/4" steel PTO shaft, or on the brass busing it slides into, as well as old stiff grease on the PTO gears. Full disassembly is required to address these issues.

I cannot stress enough to take a picture at EVERY step of the removal process.? You won't regret it afterwards.? There are four different mechanical styles I have documented produced during the C-line run....and despite having disassembled at least 30 of those now, I can still get easily confused when trying to get them back together again. Pictures?REALLY help!

Good luck!

73

Peter

VE7PS

On Wed, Dec 18, 2024 at 7:11?PM Evan via groups.io <k9sqg= [email protected]> wrote:

My guess is that the vernier drive has a lubricant that has hardened over the years. ? Same could be true of the PTO screw.? Let's hear what the experts say...

On Wednesday, December 18, 2024 at 10:07:53 PM EST, Jay W6CJ via groups.io <lastradioman= [email protected]> wrote:

Group,

In an R4C the PTO is electronically stable but that 'silky smooth' tuning is not happening.? It takes extra force to tune the PTO (as compared to my T4XC) and feels like something grabbing or resisting.

Without pulling all of the gears apart, where should I start looking for what's grabbing?

Thanks & 73

Jay

W6CJ

Victor Yes mark as shipped add the tracking # from PirateShip label that's it . Ebay sends your final value (less 13.5% ugh) and the shipping cost collected from the buyer,

?probably less the PirateShip? ??

Bill KE7KK