The AM Forum
March 28, 2024, 07:22:07 PM *
Welcome, Guest. Please login or register.

Login with username, password and session length
 
   Home   Help Calendar Links Staff List Gallery Login Register  
Pages: [1] 2   Go Down
  Print  
Author Topic: Collins KWS-1 Plate & Ant Tuning Controls REPAIR - FINAL VERSION  (Read 15999 times)
0 Members and 1 Guest are viewing this topic.
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« on: April 08, 2018, 07:32:20 PM »

Having just acquired a KWS-1 of early manufacture, I found the Plate and Ant tuning
controls to seize or be rather un-smooth. Apparently this is a common problem.

So, after checking online and finding not much good information on a repair, I investigated myself.

After determining what the problem is, I came up with a few methods to effect high quality repairs.
It's PRELIMINARY because I just wrote this up, and have yet to implement the repairs, and take pics.
I'm confident of good results using these methods.

I wrote them up, and they're in the attached pdf. (A high res version is available on request)

Comments, reactions, feedback and suggestions appreciated!

Feel free to share or put this pdf online, with attribution, please!

Repairing these knobs properly is essential to keeping these rigs on-the-air.

UPDATE: Scroll down I've posted the V1.4 PDF which contains proper information - discard earlier versions!! 6/21/2018



* KWS-1 BEAR.JPG (609.03 KB, 1480x1973 - viewed 841 times.)
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
w4bfs
W4 Beans For Supper
Contributing
Member
*
Offline Offline

Posts: 1433


more inpoot often yields more outpoot


« Reply #1 on: April 10, 2018, 04:07:54 AM »

years ago I bought a KWS1 that had worn out plate/load verniers .... It had pot multiturn counter knobs as replacement ....worked fine and looked good .... your work is better by far but this is a possibility for repair
Logged

Beefus

O would some power the gift give us
to see ourselves as others see us.
It would from many blunders free us.         Robert Burns
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #2 on: April 10, 2018, 12:44:21 PM »


Yep, I've looked at that, but the issue there is that the knobs on the typical multi-turn pot counter dial
are much smaller diameter. Also, I'm not certain but I think these resolve to 100 places vs 10 turns...
but that might be only because it's a continuously reading dial, might work out the same, other than knob
size.

Purists want the original look, of course.

Hopefully before too long I'll have pix up of the actual repair work incorporated into the pdf.

                            _-_-
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
WA2SQQ
Contributing
Member
*
Offline Offline

Posts: 1090


« Reply #3 on: April 11, 2018, 08:45:28 AM »

Very nice explanation. On my first real job I had an old German boss who was a mechanical wiz. I learned so much from him. Your explanation and the possible solutions reminded me so much of him!
Logged
nq5t
Contributing
Member
*
Offline Offline

Posts: 557



« Reply #4 on: April 11, 2018, 09:49:58 AM »

Back when I had a KWS-1, this was the most frustrating part of owning the d*** thing.  I ended up borrowing the two reduction knobs from a 180S-1 I had purchased several years before for almost nothing.  Those were in good shape.

Also, several (15?) years ago, a CCA member was selling the reduction assemblies from the PRC-47 as a solution to the KWS-1 issues.  They had the small knob, and a slightly different scale, but otherwise would work.  I bought a couple of them, but never used them .. not sure what happened to them.  In any case, my understanding at the time was that the KWS-1 assemblies had a "small" knob, too, and the large one you see is actually some kind of cap over the small knob and could be removed and shifted to cap the PRC-47 assembly.  At this point, since the older I get the less I remember, I can't say for sure that that is the case or would actually work.

It's too bad there isn't a way to install a couple of quality 6:1 verniers behind the panel with an original appearing knob.  It would make it a whole lot smoother to change bands .. without having to consult a chart first, and then cause wrist damage cranking those old verniers to the new spot.  Rapid band change was definitely not a design criteria for this transmitter … :-)

Hope you can find a good solution to rehabbing those things …
Logged
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #5 on: April 11, 2018, 09:44:54 PM »

<snip>

It's too bad there isn't a way to install a couple of quality 6:1 verniers behind the panel with an original appearing knob.  It would make it a whole lot smoother to change bands .. without having to consult a chart first, and then cause wrist damage cranking those old verniers to the new spot.  Rapid band change was definitely not a design criteria for this transmitter … :-)

Hope you can find a good solution to rehabbing those things …

There's no need for a vernier behind the panel!
As far as I can see the panel thing is a counter ONLY.
The gear reduction takes place back in the PA sub-chassis, there are gears in there.

I'll look into the PRC... yes the knob does get screwed on with a center set-screw right over a smaller
"knob" thingie.
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #6 on: April 12, 2018, 04:01:15 PM »


UPDATE #1

(will be incorporated into the final pdf...)

Pictures to follow too.
Bored the shaft hole in the knob today.
Made a holder for the lower half of the knob first.

Guess what?
Turns out the bottom half is NOT pot metal!

Or in the words of Private Gomer Pyle "su-prize su-prize, su-prize"!!

Turns out that it is actually cast brass!
The pot metal look comes from what was likely at one time a bright zinc plating
on it. That was probably to give the outer skirt's numbers and graticule lines a silver look.
Since that time, it's dulled considerably. Thus the look and feel of genuine pot metal.

Well, next to see if I can make an insert or not. Cheesy

                           _-_-

Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
w8fax
Member

Offline Offline

Posts: 55


« Reply #7 on: April 15, 2018, 09:14:06 AM »

Many years back I obtained a KWS-1 and of course the knobs were messed up. I have been a toolmaker for a hundred years, so it was a good challenge. I made a solid aluminum fixture that the knobs would sit in securely and the center located very accurately, and located radially by using the set screw hole so I could red-rill it later.. I had some end mill cutters ground to a few sizes that I thought would work to re-size the hole and repair the out of round. Then, on a Bridgeport vertical milling machine, I bored the hole out as far as I thought was safe. I then filled the back of the knob and hole with aluminum base JB Weld, avoiding the area where the gear is. By filling the void around the repair, it added some support to the wall of the hole. After letting this cure a couple of days, I re-bored the hole to the proper size, plus a thousandth or two. My fixture was made so I could also use it to re-drill the set screw. Success. I re-installed the knobs and they worked great. I still avoided over torquing them on installation tho'. Since the knobs are pretty much scrap and useless until repaired, I thought to offer my service and repair to others. Now understand, I offered this for free since I already had the tooling made up and the repair was simple. Just send me a buck or two for postage. I explained the repair that I did. I repaired a few for guys, warned them of over torquing the set screw, and they were happy to get otherwise useless parts repaired. Then....it started. I received some nasty e-mails from Collins Collector "experts" accusing me of trying to make money off of the repairs and also destroying or damaging valuable Collins parts, by rendering them "non-original". That was it. Screw it. I withdrew my offer to fix anymore at any price, and even tho' I still have the tooling somewhere I think, I stand by that decision. The repair must have worked, as I never heard of any  failures to repaired parts.  I am posting this so someone who has the skill can re-duplicate or improve what I found to be a solution and repair some otherwise useless parts to a pretty cool old transmitter.
Logged
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #8 on: April 16, 2018, 12:18:57 PM »

Heh... I suspect that many of those "purists" are now SK anyhow?

But, yeah, after more thought, It was also my idea to 'backfill' the open voids behind/around
the bore for the shaft. Yet to do that though.

I too made up a holder for the knob. I used 1.250" aluminum bar stock, and drilled, then bored
it on my lathe. I've bored the hole in the lathe after that. Seems to have come out very nicely.
I'm holding the knob in place with the set screw hole in the top that connects the knurled part to
the lower skirted dial part.

I'll have pix of the whole deal once I finish the "insert" and put it in place, and it works properly.

As far as "making a profit" off repairs? WTF does Howard Mills do??
Hard to understand what they were complaining about. I'd not have bowed out quite
so quickly on that. In fact, had I known that you had done this more or less before I came to it,
I'd have sent mine to you!! :p

But I'd have missed all the fun then! Cheesy

                                     
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #9 on: April 18, 2018, 03:05:18 PM »

Lathe fixture for holding KWS inner knob for boring.


* KNOB LATHE FIXTURE.JPG (409.87 KB, 1480x1110 - viewed 493 times.)

* KNOB LATHE BORING HOLE.JPG (404.69 KB, 1480x1110 - viewed 397 times.)
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #10 on: April 18, 2018, 08:25:50 PM »

Virtually unobtainium:



* HELIPOT R-10 PARTS.JPG (310.13 KB, 1480x1110 - viewed 546 times.)
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #11 on: April 19, 2018, 07:59:13 PM »

Updated version. V 1.2 contains more information.

The actual insert has not yet been added to the documentation.
Soon.

             _-_-

UPDATE: V 1.2 has been deleted - scroll down to V 1.4!
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
KA2DZT
Member

Offline Offline

Posts: 2192


« Reply #12 on: April 19, 2018, 11:21:54 PM »

I read your entire file.  Looks like a lot of work to fix the knob.  Your probably right about the shafts being a little short causing the failure in the first place.

I would bore the knob like you described.  Then make a new shaft that is oversize out of brass.  If the shaft has to be .250" passing through the rest of the knob assembly and panel, then turn the oversize shaft down to .250" on the part that exits the knob.  The new shaft can be short, just enough to get into the chassis area.  Use another piece of shaft material to reach the coupler.  

The new brass shaft can be soldered to the brass knob.  Or, you could carefully locate the spot where the set screw hits the shaft.  Then drill and tap the new brass shaft the same size as the set screw.  This will remove the pressure on the side walls of the bored out knob.

You can use another 1/4" union to connect together the two new pieces of shaft material.

Don't overlook using the shafts from old controls.  The pots have collars that can be pinned to the shaft.  Once pinned, turn the collar down to the size of the bored out knob hole.
Logged
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #13 on: April 20, 2018, 01:36:43 PM »

Thanks.

Your scenario was considered, and is mentioned in the pdf. Cheesy (V1.2)

There is a problem with merely boring and making the shaft end larger, and that is that the knob's bore is now
weaker than before.

One could pin a collar, but that's far more effort than needed. It's way easier to start with a larger diameter length of
stock, and turn the shaft down the 0.250" except for the part that goes into the knob. Or bore a short section of that same
bar stock to fit over the end of the 1/4" shaft. I'd turn the shaft down at the end, maybe to 0.200" then put a hole in some
stock, reamed just at an interference fit and then heat the short section, freeze the shaft, and <WACK> or press
fit them together. Then turn down that assembled piece. This way there is no slop and there is meat to take
down to fit in the widened bore (typically ends up 0.265" +/- depending on the knob).

I would not rely upon the setscrew without an insert that strengthens the brass bore. Which is why I'm not
going for this method.

At present I am doing the first insert using brass, but the next will be either steel or stainless - for strength.

Also, I have another method to add strength. That will have to wait until after I do it before it is presented.

Soldering to the knob risks overheating the knob and destroying the paint, or if it gets hot enough the zinc
plating. Also solder, at least electrical solder is prone to stress crack, so is not a great choice in that regard,
plus it is a soft metal. So, I discounted that method.

Yes, it is a fair amount of work. Most of it has been in the research, figuring out the method, and then writing it
down. Anyone with a lathe and some machining experience can knock this out in fairly short order.

The problem is that an owner of the KWS-1 with ANT and PLATE knobs that are not working well has no choice
but to repair or replace them.

In the pdf (v1.2) I've figured out and shown what the mechanism is from the OEM, an astute observer no doubt
can determine where and how to locate used, low hours examples of them. Cheesy
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #14 on: April 25, 2018, 12:53:07 PM »

Uh-oh.

Something very strange.

Was cutting a properly sized diameter for a brass insert, the first one I had made too small a diameter.
Tried it on the knob - very tight fit, which is good. Pushed and turned it to slide it on. Pulled it off.

Look at what I found!!

Yep, that's an insert made of plated brass!!
Not only that it has a hole for the setscrew and it's got markings on the surface too!
It pulled out of the knob and stuck to the piece I was machining!

So, my finding that the knob is zinc plated brass is wrong.
Yikes!

Now, it looks like the knob is cast Aluminum. Which changes everything.

More than one knob seems to evidence the brass insert showing color. Others upon close
inspection with a 10x eyeloupe do NOT. No idea what the deal is with that.

I have about 6 knobs total, most are not in good shape, fyi.

Also, with the 10x eyeloupe on more than one knob there appears to be a small stress crack on the shaft hole side next to
the gear. The crack does not appear to have migrated deeper into the shaft hole though.

So, change of plan. Looks like I'm going to go with a stainless steel insert rather than brass or steel.

Well, who knew?

                _-_-


* INSERT FOUND.JPG (248.29 KB, 1480x1121 - viewed 388 times.)
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #15 on: April 26, 2018, 12:57:07 PM »

Ok, back to where I started...

...the knobs are bloomin' alloy - likely a pot metal type alloy.
Not straight aluminum. No.
They seem to vary a bit in alloy since some knobs appear to be a bit harder than
others, but clearly pot metal.

<phew, wipes brow>

So, the brass insert MAY work, but I am leaning to steel now.
Maybe stainless, if I can machine it without too much grief.

Frankly, if anyone cares, I'm really reconsidering the insert method at all. I don't
think that even out of hardened steel that such a thin wall band will have enough strength
to resist deforming. So, I'm rethinking the idea of bonding the knob to the
shaft. No forces to do deformation.

Benefit: fast, simplest, but does not permit the knob to come off the shaft - the shaft + knob
must be removed at the coupler inside the rig.

Also rethinking the shaft diameter for using an insert!
The whole thought process up to now revolved around an unmodified 0.250" stainless steel
shaft. Maybe this is not the best idea.

The trick to putting on a larger diameter on to the shaft (not a knob insert) to meet the bored out diameter
of the knob is to permit more wall thickness by reducing the diameter of the shaft making the machined part
with a thicker wall, then affixing that OD part to the end of the now smaller OD shaft.

Now I am also giving some consideration to taking down
the shaft end to permit the use of a knob insert of (for example) 0.250" --> 0.200"
giving 0.05"/2 = 0.025" + (0.14"/2) = 0.032" wall thickness. The 0.14" is the typical bore out
diameter to make the knob hole round again. Thinking maybe taking more and going to a diameter at
the end of the shaft bringing it down to 0.150". This might give enough meat in the knob insert to let a few turns of
threads sit - that would shift the forces from the pot metal to the insert, at least in part.

Benefit: this method makes the knob still come off like a stock knob.

All this to just fix a few knobs! HA!
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
KA2DZT
Member

Offline Offline

Posts: 2192


« Reply #16 on: April 26, 2018, 02:37:36 PM »

Still think my suggestion of making short shafts from brass will work FB.  Turn the end to fit tight into the knobs.  Turn down the part of the shaft beyond the knob to 1/4".  Connect to another coupler or union just inside the panel.  Make another piece of 1/4" shaft to reach the original coupler.  Drill and tap the shaft to match the original set screw hole on the knob.  Use a small screw to lock the new shaft section to the knob.

I have a machine shop here, I could have fixed those knobs three times already. Grin
Logged
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #17 on: April 26, 2018, 04:06:41 PM »

Fred, yeah sure...

Well the method you suggested of using a short length with two couplers - there is one coupler at the
PA enclosure - is OK, but the one at the knob end will need to be very tight and concentric, since the
bushing at the dial counter is not super precise. Slop is your enemy with this dial counter.

So, no matter what you do, you're moving your machining from one place to the next.

Once you're turning down to 0.250" going an extra 5 inches isn't much of a problem anyhow, so
I'd make it all in one shot, eliminate fabricating the coupler.

But here's the problem with this idea - the knob is still prone to belling out, and once you've taken
OFF more of it, it's that much weaker. So using the setscrew is not a good option after that.

This is why it needs to be either bored out and bonded to a shaft (in which case your two part
plan would work ok, with a tight coupler), or bored and done up with a shaft end that is
reduced down to maybe 0.125" to permit ample wall thickness in the knob (to prevent further
belling out).

But I do like your idea of two parts, just that the setscrew isn't going to work.

               _-_-


When you said drill and tap the new shaft, what were you thinking?
Setscrews work by pushing against the shaft.
Were you thinking of somehow clamping instead??
A setscrew has no head, so won't do that - the hole would have to be modified, and then
ur dealing with this very soft pot metal, and a very small head.
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
KA2DZT
Member

Offline Offline

Posts: 2192


« Reply #18 on: April 26, 2018, 05:55:41 PM »

Yes, using a small (4-40 or 6-32) screw with a head which will be threaded into the new shaft.  This will put an inward pressure on the side wall of the knob.  I suggest short shafts because it is easier to turn down a short length rather than say 5" or 6" of shaft.  Especially when you down to turning a 1/4" shaft.  Depends on how good your lathe is.

As for connecting the two new pieces of shaft together, you can use a union (1/2" bar material with a 1/4" hole through it and set screws).  You can buy the unions instead of making them.
Logged
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #19 on: April 27, 2018, 09:44:22 AM »


Well, there's no way to put a 6-32 with a head into the spot where the setscrew is now.
It's already a 6-32 and the area is small.

But the idea is good in principle.

4-40? Maybe one with a small head... the setscrew hole does not have a lot of room before
you bang into the edge of the skirt. Sad

Regardless, this method using the pot metal for the head of the screw to go against will not work.
The pot metal will not stand up to the compression forces. The knob will loosen. Sad

This might fly IF one did the 0.125" shaft reduction, and put an insert into the knob, and
rather than the usual set screw, used a screw to hold as you described.

As of now I am favoring the 0.125" shaft reduction, regardless of what method I use with
it...
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
KA2DZT
Member

Offline Offline

Posts: 2192


« Reply #20 on: April 27, 2018, 12:09:28 PM »

OK,  I think I follow what you are doing.  You're going to make an insert to go into the knob with a 1/8" hole.  Then the shaft will be reduced to 1/8" to fit into the insert.  Then I guess you would use a set screw to lock the 1/8" shaft to the insert just beyond the knob.

Question is how would you lock the insert to the knob?  You're left with only the original set screw.  You can't put a lot of pressure on the pot metal.  You can still locate the position of the set screw on the insert.  Then drill a shallow hole in the insert.  This will allow the set screw to go into the insert a little bit to improve the grabbing the insert without having to use a lot a pressure on the set screw.

I hate pot metal.  The stuff causes all sorts of problems.
Logged
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #21 on: April 27, 2018, 06:24:34 PM »

Two options:
- anaerobic shaft lock (a Loctite commercial product for machine tool shafts) which is my first choice.
- slow set epoxy

I'll get the set screw hole in the insert to take a few threads from a tap. Cheesy

Yeah pot metal blows chunks, usually.

 
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #22 on: June 21, 2018, 09:24:19 PM »

Phew!
It really wasn't a lot of man-hours, but quite a lot of elapsed time.
Finally got a design that works, built and tested!
It's good.

Maybe more than many can do at home, but I think the "bonded" version on the 0.250"
shaft can be done without a lathe, probably just with a drill press, a good eye and careful
set-up.

Your thoughts and comments appreciated, as are mentions of errors and/or points that are
unclear (I wrote it, it makes sense to me, right?)


A high res pdf is available via email - just ask. The pix are better in the high res file.


                           _-_-bear

* Repairing the KWS KNOB v1.4.pdf (460.07 KB - downloaded 258 times.)
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #23 on: July 12, 2018, 10:47:55 PM »

Did the second of the two knobs as a bonded version.

Came out fine.
Of course to take the knob off, one has to remove the shaft, the shaft collar from inside
the rig. Not terribly difficult, and no need to do it often if ever.

I ended up using slow set steel filled JB Weld.
It was available, so I used it.
Still did the piece of wax melted with a heat gun down at the bottom over the screw.
I figure you never know when you might for some unforeseen reason want to remove that
shaft... no need to bond the knob cap's screw so that it can never ever be removed.

Anyhow it came out fine. I was able to square it up just about perfectly on the lathe.
It set overnight. Got the shaft length just about perfect too.

Came up with a way that folks with only a drill press might be able to do this method!

The trick would be to find a way to put a shallow conic point on the end of the 1/4" shaft that
goes into the knob. Do the same wax covering of the screw. It would be best by far to use
a button head cap screw. That has an allen wrench hole in the top, and has a lower
profile head than the filister head that is stock. You DO need to take the diameter down so that it
is less than the hole diameter and it will fit all the way down the shaft bore.

By mounting the screw onto a 6-32 metal threaded standoff and putting that into the drill press,
you can use a file to remove the diameter.

The most difficult part is to make a good conic point on the end. It can be rather shallow and not
terribly pointy (not pencil point like). The idea behind the "point" is that the entire repair depends
on the shaft being centered on the knob, and the plane of the skirt being perpendicular to
the shaft.

The point indexes the shaft to the center of the allen/hex in the screw head, which will be in close
tolerance to the true center of the knob. Then by putting the shaft into the chuck of the drill press, the shaft will
be inserted as perpendicularly as the drill press set up is! Cheesy

(there are ways to check the squareness of a drill press)

But, most drill presses ought to be sufficiently square for the repair to work. At least that's
the theory here.

                   _-_-

PS. Idea: a grinder with a jig, like a drill sharpening tool, could be used to make a rather accurately
centered (shallow) point.
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
Opcom
Patrick J. / KD5OEI
Contributing
Member
*
Offline Offline

Posts: 8308



WWW
« Reply #24 on: July 14, 2018, 08:44:10 PM »

I am glad you are thinking this out so well instead of rusing a job like many others do.
Logged

Radio Candelstein - Flagship Station of the NRK Radio Network.
Pages: [1] 2   Go Up
  Print  
 
Jump to:  

AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
 AMfone © 2001-2015
Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Page created in 0.068 seconds with 19 queries.