Another rig question

[AF9J]

Hi everybody, as you some of you know, I'm looking for some better AM iron/gear than I have at the present time.  I also mentioned that I can't run more tha say 50w of carrier, if I don't want to risk the wrath of my neighbors, in my apartment building.  I'd like to thank everybody for the input on the Gonset G-76.  I will keep an eye out for one.

Here's some additional info.  Money is pretty tight for me at the present time (I'm paying off thousands in bills that were racked up during hard times a few years ago), and will be for some time (hence the reason why I'm stuck with some less than desirable gear at the present time).  So, I'm always on the lookout for ways to get decent AM gear on the cheap.  So, with that thought in mind, I may have to forego the G-76, and maybe get a transmitter, and use my ricebox rig as a receiver (until I can dig up the money for en economical [but NOT 100 lb weight!] receiver that does decent AM).

Today I saw on e-pay a couple of Johnson Challengers, going for OK prices (well under $200 at the present time).  Other than the fact that the Challenger is crystal controlled (which means scrounging for a VFO, or a box of rocks), and will do 40W on AM, I have no idea how good it is.  Is it a decent rig, or is it a dog?  Also, what are your thoughts on other cheap (just in cost - not performance) AM transmitters that will do the job (and no, I'm not afraid to open them up, and work on them, I do all of the servicing on my Swan and Kenwood tube rigs)?

73,
Ellen - AF9J

[WQ9E]

Hi Ellen,
I am assuming your QTH is still in WI as per QRZ.com.  If so, why don't you check into the Midwest Classic Radio Net (it meets on 3885 Saturday mornings and Rob WA9ZTY is the net control located in Marshall).  Use your rice box on AM and let it be known what sort of rig you are seeking and I bet you can come up with something closer and much less expensive than the Ebay route.  It is a friendly net and it is focused on use, sales and acquisition, and restoration of AM gear.

Hope to hear you on the net Saturday!

73, Rodger WQ9E

[AF9J]

Hi Roger, 

Thanks for the info.  Yes, my QRZ address is current (I live in the MIlwaukee metro area).  I'll do that.  I was wondering if there was an AM net around here.  More than likely, I'll use the Swan.  I'm not happy about the overshoot in my FT-897D on transmit.  Even when running it at 20W of carrier, keying the mike, spikes power to about 30 Plus watts (it's only supposed to be rated for 25W of carrier), for a couple of tenths of a second, until the ALC kicks in.  No thanks!

73,
Ellen - AF9J

BTW, any ideas for a lower cost tranmitter?

[W1GFH]

BTW, any ideas for a lower cost tranmitter?

For some reason the Johnson Challenger does not have much of a following. Can't say why, never had one, never knew anyone that had one.

Assuming you want to avoid paying the toll for the popular (and pricey) classics like Viking Valiant, Ranger, Heath DX-100, etc.

• Many people swear by the Heath DX-60 as a low-cost (eBay prices $80-$130), fun, easy to tinker-with AM rig:

http://oak.cats.ohiou.edu/~postr/bapix/DX60.htm

• Then there's a Multi Elmac AF-67 or AF-68 (eBay, about $120):

http://www.qsl.net/n9bor/Multi-Elmac.htm

You might be able to get a Heathkit Apache for near $150. Big rig, but can be made to sound very hi-fi. And the Globe Scout is a very sweet looking little transmitter and easy to tinker with. I'm sure we can think of a few more.

Yes...eBay is a LAST RESORT. Hamfests, AM swap nets, and "Buddy Pricing" is best.

[KB2WIG]

http://cgi.ebay.com/Heathkit-DX-60B-Transmitter_W0QQitemZ120102757514QQcategoryZ4675QQrdZ1QQcmdZViewItem

for what its worth.....  klc

[w3jn]

Keep an eye out at hamfests.  Ugly yet very serviceable transmitters are still around for reasonable prices.  I've passed up MANY $30 DX-100s.

[WZ1M]

Be careful when buying a DX-60/B, the function switch is a BIG problem and hard to find. There is an easy fix if your switch is still ok.
Gary...WZ1M

[W1GFH]

Oh yeah, I forgot to add:

...an economical [but NOT 100 lb weight!] receiver that does decent AM).

I urge you to look into the National NC-300/303.  1960's built. Semi large, but fairly light, 60 lbs.  Stable, accurate sliderule tuning (rather than romantic but impulsive "where am I?" half-moon-dial tuning) and REALLY nice AM audio (although purists complain that it won't widen out to 16 kHz).  

[kf6pqt]

I'll take all those $30 Dx-100's please!  I'll even pay shipping!

[W1GFH]

I've passed up MANY $30 DX-100s.

Yeah but I think she wants a rig without zorched transformers, pots ripped out, rust, slime, and cat pee smell

[AF9J]

Yuppers!

I don't mind servicing my rigs, and even doing a few mods that are recommended (I do/did it on my Swan 270B, and Kenwood TS-820).  But I don't have the time, equipment, or finances to rebuild a rig from the ground up.  Also, while I've read of things that can be done to greatly improve the DX-100, I don't have the space for a 70-100lb transmitter.  Dimensionally I'd say sizewise - like a Johnson Ranger (but they sure have gotten expensive since I paid $150 for the one I briefly owned 12 years ago) would be best.  With some creative rearranging, maybe a Knight T-150 at the most sizewise.  I'd even consider a DX-35 or DX-40, if it's cheap.  Weightwise - I don't want to have the just about throw out my back to carry the thing (you ever try carrying a Fender Twin or Mesa Boogie tube guitar amp?  They push a 100 lbs!  That's one of the reasons why I don't have tube guitar amps anymore [besides you can get  cool sounding mega distortion out of some of today's solid state guitar amps]).

73,
Ellen - AF9J

I've passed up MANY $30 DX-100s.

Yeah but I think she wants a rig without zorched transformers, pots ripped out, rust, slime, and cat pee smell

[WD8BIL]

Ya know Ellen... the Swan can be made to sound pretty good. Might you consider a linear for the ol' girl? That'll get ya into the 100 - 200 watt class as you research and decide on a good boatanchor.

[W8EJO]

I'd steer clear of the Challenger. IMHO it was EF Johnson's wost effort. TV tube final, screen modulated, crystal control - who needs it.

If size is an issue, I would echo what others have recommended - Multi-Elmac AF67 or AF68. 6146 final, built-in VFO. Many out there, decent prices, small size, separate power supply, they sound good on the air. They were known as the poor man's Johnson Ranger many years ago.

My 2 cents

Terry
W8EJO

Yuppers!

I don't mind servicing my rigs, and even doing a few mods that are recommended (I do/did it on my Swan 270B, and Kenwood TS-820).  But I don't have the time, equipment, or finances to rebuild a rig from the ground up.  Also, while I've read of things that can be done to greatly improve the DX-100, I don't have the space for a 70-100lb transmitter.  Dimensionally I'd say sizewise - like a Johnson Ranger (but they sure have gotten expensive since I paid $150 for the one I briefly owned 12 years ago) would be best.  With some creative rearranging, maybe a Knight T-150 at the most sizewise.  I'd even consider a DX-35 or DX-40, if it's cheap.  Weightwise - I don't want to have the just about throw out my back to carry the thing (you ever try carrying a Fender Twin or Mesa Boogie tube guitar amp?  They push a 100 lbs!  That's one of the reasons why I don't have tube guitar amps anymore [besides you can get  cool sounding mega distortion out of some of today's solid state guitar amps]).

73,
Ellen - AF9J

I've passed up MANY $30 DX-100s.

Yeah but I think she wants a rig without zorched transformers, pots ripped out, rust, slime, and cat pee smell

[AF9J]

Hi Julius & Terry,

Julius, actually for now, I have the Swan 270B set up for AM (It may not be DSB AM like my FT-897D, but it doesn't have the ALC overshoot problems my FT-897D has, when you first key the mic).  I'd prefer not use it long term for AM.  A friend of mine who is a Swan nut, told me some time ago, that while the 270B does OK AM (about 30W of carrier), it's kind of hard on the sweep tube that's used for a final.

Terry, thanks for the info on the Challenger.  It pretty much confirms some other info I read online about it - that it's not a very good rig.  Yeah, the Mult Elmac AF67 & AF68 have been added to my list of rigs to watch for.  The main issue with them, is finding a power supply that you don't have to majorly modify to supply the 22V the modulator drivers need, or for that matter, the dedicated power supply sold for these rigs (they're kind of hard to come by).

Another note to everyone - I'm willing to settle for crystal control for now (and then build or get a VFO later on), if it'll get me on AM sooner, with an OK transmitter, at a low cost.

73,
Ellen - AF9J

[Todd, KA1KAQ]

The trick to using the Swan on the air is to get everyone on the 'average' frequency, which lies between the high and low drift points.

'JN is right on the money with the DX-100s. There are a lot of them out there, some better than others and some reasonably priced. I saw a nice one in a surplus shop in Portland OR when I was out there a while back, looked like new and could be had for around $50. Luckily I lacked the time and ability to deal with shipping.

Apaches show up often too, last one I saw was at Hopkinton last fall, for $100 including a pair of Aperex Bugle Boy EL34 modulators. Was in decent shape and worked.

Just be sure to eat your Wheaties before moving them....

[The Slab Bacon]

Julius?? Hmmmm.....................

[Todd, KA1KAQ]

Julius?? Hmmmm.....................

Et tu, Brute?   

[Pete, WA2CWA]

Another cool rig you might want to consider is the Heath Cheyenne, MT-1 transmitter. Although it requires an external power supply that shouldn't be that difficult to find or build. There's one on ebay now for $15.50 with 9 hours to go. There's also a matching receiver for it called the Comanche, MR-1.




Here's K2CQK's Heathkit Cheyenne and Comanche:

[AF9J]

Hmmm,

Now THAT is interesting Pete.  I put it on my e-bay watch list.  All it needs, is a power supply.  The band switching on it looks like the same type of switching as the HG-10B VFO I used with my HW-16 as a Novice.  Oh, BTW, I also noticed Knight T-60 on e-bay, going for $60 on e-bay.  Anybody have any thoughts on it?

Oh yeah Todd, about the Swan - drift?  You must mean the 350 or the 500   MY 270B is stable after about a 15 minute warmup.  It also has killer audio.   You guys are great!  Thanks for all of the suggestions!  Keep em coming!

73,
Ellen - AF9J

[w3jn]

The CHeyenne is basically a DX-60 with VFO but minus the power supply.  Single 6146 screen mudulated.  One of the Heathkit HP32 power supplies (intended for the SB102 etc) work Fine Business.  The normal DX-60 mods apply to this xmitter as well.  It's harder to work on than the DX-60, but has the advantage of having a nice stable VFO built in.

The matching receiver is essentially junk and not worth considering for AM use..

[AF9J]

I have a watch on it as we speak. With 1 hr 50min to go, the high bid is just under $23.  Unless somebody snipes me in the last minutes, I could pick this up dirt cheap.  I also have a watch on a DX-60B on e-bay that's in Sheboygan (about 40 miles north of here).  That rig, I could pick up myself, saving on shipping.

Both the Cheyenne and the the DX-60B are a horse a piece:

Cheyenne 

Good - already has a VFO, chance to get it dirt cheap

Bad - need to scrounge up a power supply for it, harder to work on than DX-60B, since it's a 50s rig; it uses the "plain" 6146, instead of later and much more plentiful 6146W (which I retubed my Kenwood TS-820 with last year), oftentimes earlier Heathkits don't neutralize properly with the 6146W.

DX-60B

Good - built-in power supply, possibility of picking one up nearby; saving on shipping, easier to work on than Cheyenne, the one nearby has been refurbished in recent years
 
Bad - no VFO (HG-10B is getting harder to find, and expensive to boot).

73,
Ellen - AF9J

[AF9J]

Yehaaa!  I just won the Cheyenne!  My winning bid was $42.11.  Now I have to wait for a shipping cost on it.  Well, I'd better get some sleep.  BTW, anybody know what the mic impedance is?  I hate the mic that's coming with the rig.  Strangely enough, I prefer either hand mics, or and Astatic D-104 like I had back in 1995 (I assume it would have to be high impedance).

73,
Ellen - AF9J

[KB2WIG]

 here ya go              http://bama.edebris.com/manuals/heath/mt-1/

    "  Microphones

Since mobile operation demands that properly shaped audio response be
employed, a vary carefully designed ceramic microphone is included with the
MT-1 "Cheyenne" Mobile Transmitter. This is to insure very effective
modulation with plenty of "punch". The microphone serves to suppress all but
the upper middle range of the voice frequencies and the audio system, as
described above, is designed around this response. If other microphones are
used, it may be necessary to alter the circuit components and the modulator
for best results. In any case, the microphone should be a high impedance type
and preferably ceramic, since crystal or carbon microphones can be damaged by
the hot sun to which they are often subjected in mobile operation.   "

[W1GFH]

Yehaaa!  I just won the Cheyenne!  My winning bid was $42.11.  Now I have to wait for a shipping cost on it.  Well, I'd better get some sleep.  BTW, anybody know what the mic impedance is?  I hate the mic that's coming with the rig.  Strangely enough, I prefer either hand mics, or and Astatic D-104 like I had back in 1995 (I assume it would have to be high impedance).

73,
Ellen - AF9J

Wheeee! Congrats. Now the real fun begins. There are plenty of Heathkit HP-23 power supplies available on eBay for bargain prices, but the HP-20 used by the Cheyenne seems rare as hens teeth.

Googling around, I see that Cheyenne owners were wrestling with the problem a decade ago:

>I realized that the cheyene requires 600V and the hp-23 provides 800V.
>Any ideas on how to make these work together?  Thanks for reading.

Even if the Cheyenne has a 6146 (or two) in it (as do the radios that
originally used the HP23-series supplies), part of the problem may be that
its final tank circuit was designed for best operation at the lower
voltage. No-load voltage of the HP23 may be as high as 900 volts
(especially on today's high AC line voltages) and you'd have to carefully
check everything in the Cheyenne's high B+ line to make sure it can handle
at least that much. Perhaps the final's screen supply is via a dropping
resistor instead of directly from the low B+? In that case, you'd want to
change that, either the dropping resistor itself or shifting it over to the
LV B+ supply.

Then, too, look at the original low B+ requirement: is it actually what the
HP23 provides or somewhat lower (such as 200V original vs the switchable
275/350 from the HP23B, or 250/300 from the older HP23)?

And how about the bias supply? And any relays in the Cheyenne? Does the
Cheyenne have any relays running from the bias supply, and thus capable of
exceeding the HP23/23B's bias supply rating? You're probably OK on the
filament supply current requirement but it wouldn't hurt to check that out,
too.

You need to go through each and every one of these if you don't want to
cook something in the Cheyenne or power supply. You *could* use a variac on
the AC supply except that'd probably reduce the filament voltage and maybe
the bias voltage too much. Then again, perhaps you could find a happy
compromise, such as reducing the AC input voltage to where the filament
voltage dropped from a nominal 6.3 to only 5.5 or so (or 12.6 to 11.0),
which is a drop of about 13% which would drop the HV from a nominal 820 to
715, not too bad (of course, the LV will drop the same). No variac? Try a
filament transformer wired as a "bucking" transformer; I do that for my
shop lights now and that's caused my lights to last a lot longer than the
usual 3 months or so than on the full AC line voltage.[/i]

(PS: The Electrovoice "banana" mike: seem to recall it was ceramic, hi-Z.)

[The Slab Bacon]

The matching receiver is essentially junk and not worth considering for AM use..

Yea, what he said!!
I had one of the receivers it is a real P.O.S. Too narrow of bandwidth (fixed crystal lattice filter) Piss poor AGC action, and horrible dynamic range. You would have to reinvent the wheel to make it tollerable for serious AM. I got rid of mine quickly.

                                                    The Slab Bacon