Albacore continued

[MFR1964]

Mark,

I did the same trick with the 212, placed the adf in front with the batteries, mine was also twichy near the e motor, i certainly would place the third capacitor, to me three capacitors is always standard configuration, it keeps the buggs out.

[Subculture]

Have you heard of x2y components?

I found out about these a few weeks back when searching out some information on better noise suppression.

Basically they do the job of the three capacitors, only much, much better. They've been around since the mid-nineties, and apparently are used in a lot of equipment, and are used extensively in the automobile industry. There are some very good technical documents on suppressing motor brush noise, and it shows in the free pdf download the main sources of emission and what to look for in a quality motor.

http://www.x2y.com/

http://www.x2y.com/techlib.htm#dcpub

[He Who Shall Not Be Named]

Andy, I could not get to those sites. Anyone else haveing that problem?

[trout]

Nope. Got to them and going to research more. This is good stuff.
see if this works:

http://www.x2y.com/publications/dcmotors/feb14-05.pdf

[Subculture]

All okay that this end, Dave.

If you want a supplier for these, Digikey sell them in small quantities. They get a lot cheaper if you purchase them by the thousand, but you're going to have to build a lot of models to use that lot up. They do work out more expensive than ceramic caps, but they do a much better job of quenching brush noise, which if you look at the graphs in the literature will show you is very prevalent in the frequency range our radio systems operate at.

There is also some very good information on best motor designs. You will soon notice that the mabuchi style motors we often use are pretty poor in this respect, but can be modified quite simply to produce much improved noise performance.

here is a graph showing the difference. the green part represetns a standard three cap suppression set-up. the x2y reduces the noise by about 25-30db, whcih is very large reduction-

[trout]

Subculture, how did you search for them? I seem to have trouble finding them. Update: found them

http://www.digikey.com/product-search/en/kits/passive-capacitors/2490603?k=x2y%200402

Not sure which one would work for out models (yet)

[Subculture]

The advice given is to start with a 400nF x2y, 50 volt rating is more than sufficient for our needs, and the 1410 package is a manageable size- http://www.digikey.com/product-detai...7-1-ND/1556422

[Subculture]

BTW, if you want to order a few up, I don't mind coming in with you, and we can split the postage costs then.

[He Who Shall Not Be Named]

Andy, thanks for the graph -- makes your point. With that drop in noise amplitude, these 'new' cap's might permit us to us the cheaper receivers in the tightly crammed SD's. You're work to pass on relevant information to the rest of us is most appreciated. Yours is one of the names I look forward to when logging in -- always great stuff to know.

Mike: We gotta look into this -- We're good with the 3.5 SD's and the traditional .01 micro Farad cap's, where I can keep the receiver well distanced from the motor(s); the inverse-square-law works for us when we have the room to exploit it, but this level of noise suppression (Andy's magic cap's) might let us get away with using the less selective receivers in our smaller SD's were all the gizmos are piled one-atop-the-other.

How bout it, boss?

David

[Subculture]

They work as a balanced component. Any interference on one side, has an equal and opposite counterpart, and they should snuff one another out.

Basically for your average cheap far east electric motor, the things you have to do are -

1. Ensure any air slots for cooling are capped off with a metal shield.

2. The end cap of the motor should metal, if not then it should be capped off with something metallic and conductive, and this needs to be soldered to the can.

3. The connections to the motor need to be moved so they are as close together as possible.

4. The x2y component needs to be mounted directly across the connections leading out of the motor.

Further information- http://www.x2y.com/publications/dcmotors/nov1-00.pdf

1-3 are usually done for you already if you have a very high quality motor like a Buhler, Maxon, Pittman, Portescap etc. I realise equipping WTC's with these motors commercially would push the price beyond what most people are prepared to pay, and they only make economic sense when purchased as surplus items. So if you're growing your own WTC, then it's worth looking out for these quality motors.

Provided the above items are taken care of, the graphs show that the x2y attenuates noise close to normal ambient conditions e.g. no motor there. I'm sure there are other factors at work too, and I'm concious of the fact they have a product to sell, but it does seem to be a worthwhile mod to try if you're experiencing problems with interference and/or glitching.

[He Who Shall Not Be Named]

Thanks, Andy. My education continues.

David

[greenman407]

Status Update. Well I tried the second ADF2 and the terrible glitching is still there. Totally unacceptable. So, I mounted the ADF2 inside the front compartment. This required some extra work. I had to run a CAT-3, 6 conductor wire up thru the conduit between the forward and rear compartments. This reqd. soldering and heat shrink wrap. The end result was a sucessfully operating pitch controller.Much less vibrations in the front compartment. The new speed controller seeems to be of good quality and as a bonus........its waterproff to boot. Trimming the boat was also involved. I went back and did some research. The last time I trimmed this boat it was on the ocassion of trying to eliminate a porpoising in the water. I had found that the balance point of the sub was 3&1/2" ahead of the center of the submarine. I moved the balance point back toward the stern by 1" and this improved the boats handling. So, this time I resolved to move the balance point back to 1" in front of the center of the submarine.. This will be our starting point. Since this sub is being retrofitted for the soul purpose of making it capable of higher speeds routinely, it needs good stability to start with. So with the addition of more weight in the rear, more foam was reqd. to get the back end up. My Moms bathtub is the perfect test tank for such a small submarine. Ill get a picture of the foam and weight locations later. My plan is to get this boat in the water proper for her shakedown cruise next Saturday. In the meantime Ill get her back in the test tank for finall adjustments and prep.

[greenman407]

Todays update. Today was the first test of the drive. Its a little stiff. Itll need to be broken in a little bit so that it will become smoother as time goes on. Here are some pictures showing.........stuff. I will post a video of her shortly.

[greenman407]

As Promised. Here is a Workshop video of it.

http://www.youtube.com/watch?v=ATXLJ7tYMqY

[He Who Shall Not Be Named]

Excellent job on the video (the ALBACORE ain't bad either). Keep packing grease in those roller bearings and you're good to go. this thing will be a screamer, Mark. Can't wait for a patrol report.

David