The AM Forum

I was once active in HF AM several years ago but haven't been on the air in sometime (except for a few SSB contacts).  I am diving into VHF AM and have stirred some interest among a couple of local hams for some 2 meter AM action.  In regard to 6 meters, my M2 three element 6 meter yagi arrived this evening from DX Engineering and it will be mounted on my 35' tower.  My Ameco TX-62, Gonset Communicator IV, Knight T-60, and Lettine 242 are my primary 6 meter AM rigs (the latter is plate modulated and a fun rig to operate).  I can press my HT-40 into 6 meter service but I generally use it on 10 meters.

My Gonset GC-105 2 meter AM transceiver is in the process of being recapped and aligned.  I plan to mount a Cushcraft 13B2 2 meter beam or two 8 element Cubex 2 meter quads in phase about 4' above the 6 meter beam--I haven't decided on the antenna yet.  Hopefully I'll be able to make a few contacts.  Two meters AM has been an interest of mine and perhaps others would be interested as well.  We will see...

Chris, N4JOY

Hiya, Chris.
As I've been slowly accruing (and refurbing, as necessary) a fair amount of Boatanchor-class rigs lately, I've come up with a few that'll work 2 meter AM.  After poring over all the neighboring areas' bandplans (I'm in western NC, right where I-40 crosses I-77) and an unanswered email to the repeater coordinator for my area, I've come up with bupkus for officially-sanctioned freqs to use for AM on 2 meters.

What I *think* will be the best 2m AM tx rig from my stable will be a near-mint Amplidyne TX-621 (6, 220, and 2m).  I've got the matching TX-221 VFO, but to get on 220 I need an add-in assembly, called (I think) the TX-261.  The main TX has switches and drive/load/peak adjustments for when that module is present, but for now I'm limited to 2 & 6 am with this rig.  I fear the TX-261 was made of Unobtanium, so confidence here is not high on that point.

Have you come up with a concensus there as to usable freq(s) on 2m AM?  I was thinking somehwere in the 144.2 to 144.44 range (a couple of channnels in there are used as 2m simplex dump-out links from a UHF repeater empire up here.

I see you're about 580 miles almost directly south of me, and sometime when the band is forgiving, I'd be happy to try calling for you on a sked.

First requirement though, I think, will be to find some place where we're not run off by the weak signal folks, sat links, CW-only places, etc.

So whatcha folks got down there?
73,
-- Stu kl7hny --

You guys might want to read this:
http://amfone.net/Amforum/index.php?topic=33419.0

Pete,
Many thanks for the link.  I'd tried using the forum's Search function, but depending upon how I set it up, I got either zero hits or about 6,000.
I think I've even got a rock in the Amplidyne for 144.270 -- woot!

tnx agn es 73,
de kl7hny
diddly dahdidah
dit     dit

Chris,
In all my recent bouts of G.A.S. ("Gear Acquisition Syndrome", a bassists' technical term) I've somehow neglected coming up with anything yet to actually *hear* on 2m AM.
This week I'm driving to SC to pick up my "new" EFJ Viking I & Hallicrafters SX-111, but that'll only get me onto HF.
I'm currently fiddling with modifying an old-ish (although not as old as anything else I've got) tunable Realistic high & low band FM monitor.  I'm trying to cobble together an AM detector to feed out of the first I.F. amp so it isn't yet amplified into limiting and put in a narrower Murata filter.  If I can get it to detect AM with decent sensitivity, I think a helical filter in front of the antenna input might keep it from hearing everything from airplanes in flight to British TV audio.....

Or maybe I'll luck out and come up with the appropriate dedicated 2m AM xcvr, or a converter for one of the existing Hammarlund rcvrs on the shelf here.  The two Heath Towers that I've got hear pretty much one solid block of RF noise because of all the FM repeaters nearby.

Now that I've found this site, at least there's a predictable place where I can search for resources.

I'll see if the treasure trove I'm acquiring also has parts to build up a 2m receiving converter. 

73 for now,
Stu   kl7hny
diddly dahdidah
dit    dit

Be aware many older 2 meter receivers and converters do  not have enough selectivity to deal with stuff found on modern communications towers.

Helical resonators are your friend.

A good 2 meter converter is the Ameco CN-144.

(http://www.virhistory.com/ham/kits/ameco/ameco-cn144-01.jpg)

An even better converter, if you can find one, is the AZL 2 meter converter. Construction info is in QST (somewhere around 1959).

(http://www.tnt-net.ca/ve6kq/w2azl_1.jpg)