Direction in Setting Up Station

[KC4VWU]

Hi All,
         I have recently made my first couple of contacts on AM. I dug out the basket case Hallicrafters HT-32 that I had bought in pieces several years ago and put it back together. I pulled the plate and L.V. rectifiers and repalced them with solid state pieces mounted in some surplus octal bases complete with dropping resistors to keep the voltages in line with factory specs. I also added PTT capability, and built a homebrew T/R relay with enough poles to switch the antenna and mute the receiver, etc. The receiver is a National NC 2-40D and works reasonably well despite nearby slopbukit activity. I am presently running a Turner +3 mic. Now that I'm to this point, I'm a little foggy as to which way I need to proceed from here. I have a Heil Goldline that I purchased a year or two ago and tried that, but of course it sounded horrible and I expected that. I'd like to get this setup sounding great BEFORE I add an amplifier, since that situation would only make things worse. What equipment should I look for audio wise? Will the HT 32 be capable of producing quality audio? I also have a Viking II which will have to be "gone through". Would I be better off turning my attention to the V II and putting the Halli on the back burner? I really need a little guidance in getting a good quality signal out there since I am a newbie at this. Any help would certainly be appreciated.
Thanks, Phil - KC4VWU

[W3NP]

While the HT-32 is a nice looking unit, it is primarlily an early SSB/CW transmitter with low level AM added at a reduced power level much as with all of the early SSB rigs.
My opinion is, since you are interested in good audio, would be to concentrate on the VII. It is much easier to work on, can with some simple mods make very good sounding plate modulated AM at 100 or so watts output. It will work well with a straight unamplified D-104 mic. It also covers 160 meters which, if you can get an antenna up, is a great wintertime AM band.
It will pair up nicely with that particular National RX.

IF you decide to get the Viking up and running, I would concentrate on just getting it working as it was originally built before doing any mods. Just replace the electrolytic caps, the HV cap is oil and will probably be ok. My VII still has vacuum tube rectifiers and works FB.

The HT-32  will make a nice vintage SSB/CW setup when paired with a similar period RX

[WQ9E]

Phil,

I am agreement with Dave on this.  The HT-32 is a nice transmitter but the V-2 is the better choice for AM.  You will want to find a VFO for the Viking 2 or you will be spending a lot on crystals!  The matching Johnson VFO is nice but the more common Heathkit VF-1, the Allied/Knightkit VFO or others will work as well.

I just recently put another Viking 1 on the air.  It needed new electrolytic caps in the low voltage and bias supplies (the HV cap is oil like you Viking 2 and these rarely need replacement) and the electrolytic cathode bypass caps in the audio section also needed replacement.  There are a lot of mods out there for the Vikings but the audio is just fine stock.   There was a factory update you might consider if you have an early unit, Factory Mod. A added a 6AQ5 clamper tube to early production Viking 2's, and Factory Mod. B slightly modified the audio section for better low frequency response.  There should be a 10 uf cathode bypass on tube V-2 (2'nd audio stage) if yours was a later unit or has Mod. B installed.  Johnson also published an update which added grid blocked keying to the Viking 1 and 2 but this is a very extensive modification and even if you operate CW extensively (I do) you don't need it.

The Viking 1 and 2 are both very rugged transmitters and are pretty simple to work on.  In addition to the electrolytic caps check/clean the tube base and sockets of the 5R4 rectifier tubes because there is a lot of voltage present here and any dust will cause carbon tracking and arc-over.  Make sure the proper sized fuse is installed and a previous owner didn't put in whatever was convenient.  The 6146 final tubes are rugged but don't over drive the grids; 5 to 6 mils of grid current is plenty.   If the drive control pot goes bad there is a modification for the DX-100 drive pot to use a transistor plus small control pot that is published on the AM fone website, the original wire wound pots are expensive and difficult to find.  Although several places sell what they refer to as 4 watt rated pots which appear to be the proper replacement for the original if you read the fine print that 4 watt rating is at very low ambient temperatures and it is de-rated to 1 watt at typical operating temperatures.

The NC-240D is one of my favorite receivers, very cool looking with that convenient switch selection of bandspread ranges.  Properly aligned the crystal filter can be useful under "battle conditions" on AM.  I have a couple of NC-240D receivers and a couple of its predecessor NC-100X's paired with various transmitters and they are very good for such early build equipment.  Of course with an HT-32 you should also be on the lookout for the matching SX-101 series receiver and these are great receivers at fighting QRM on AM.

Happy vintage AMing!
Rodger WQ9E

[AF9J]

I agree with the others.  The Viking II is the way to go.  I restored one last March, and i pair it with a Drake R-4A.  It's a relatively easy transmitter to work on.  If yours is like mine, it may already have the factory approved PTT mod installed.  I'm kind of lazy with mine, in that I have both a crystal installed (for 3885 kHz, which is a common use AM freq.), and I use a VFO.  The Viking II isn't picky about VFOs either.  You can use the Johnson 122, but I use a Heathkit VF-1, with good results. Mic-wise the Viking II is also very forgiving.  I just use a plain-jane D-104 with my V2, and get good audio reports.  In general, the Viking II is a very sturdy, in some ways, overbuilt rig.

73,
Ellen - AF9J

[KC4VWU]

Thanks to Dave, Rodger, and Ellen for the replies and advice. This afternoon, I lugged the Viker from the storage building to the shack. An initial inspection has revealed that it has been recapped, less the high B+ oil filled, and it appears that no mods have been done. I'll have to get a parts list together tomorrow and  review all the necessary mods to bring it up to speed on reliability before I fire it up for a test. Where could I get a copy of the kit build manual?
Thanks, Phil KC4VWU

[W3NP]

The Viking II manual is available on Bama. I believe this is the complete manual:  http://bama.edebris.com/manuals/johnson/viking2(2)/

Johnson manuals were NOT like Heathkit manuals as far as construction details.

As I mentioned before, I would not do any mods until after you determine that the unit is in basic working condx. Then do them one at a time. As Rodger said, the Viking II doesn't sound half bad stock. You could increase the grid resistor on the 1st speech amp to around 4.7 meg or so (for use with a crystal D-104), fatten up a few coupling caps - things like that, but wait until you check it out first. Make a few contacts and get some good baseline info as to how it sounds now.

If you get any arcing or sparking from the rotary inductor, stop and give it a good cleaning with alcohol or some non-residue leaving solvent before you use it any more.

[ve6pg]

phil...ya, the viker is a good way to go...but if you want any further help on setting up a station, do yourself a favour, and dont ask me...that is unless you want to create a space of complete chaos, cant find anything, coffee cups all around, many scraps of paper, power bars all over, etc. etc..

tim..

..sk..

[N3DRB The Derb]

best mod for a  viking 2 is getting rid of the pissweak interstage driver transformer an go phase splitter or good diver transformer using a 6B4 ( I think ) which is a 2A3 in mini 9 pin form. a single 6C4 gain stage will need to be added and once the gain is set, forgotten about.

[WD5JKO]

Phil,

   I agree with the others in that the Viking II will be easier to make decent AM than the HT-32. That said, a low level AM rig can be Tailored to make excellent AM, and is arguably equally/more capable than plate modulation done with an interstage + modulation transformer. So don't toss that HT-32. When combined with a SB-220 it will do 300+ watts AM, or with one of those 4 X 572B linears, maybe 200- 250 watts AM.

    I combine a highly modified Central electronics 20A with a Gonset GSB201 to make decent AM and with the flick of a switch I can chase off offending SSB that has zero'd in on an AM QSO. Low level AM sometimes gets a bad wrap, IMHO.

73,
Jim
WD5JKO

[W3NP]

Phil,

 Low level AM sometimes gets a bad wrap, IMHO.

73,
Jim
WD5JKO

The issue at hand was not low level vs high level AM or the virtues of either. Lots of guys/gals use low level generated am with good effect.
The issue was that a relative new comer to AM wanted to know the best path to getting on AM with a decent signal, and with the choices he has, the Viking II would be the simpler and easier path to take, at least initially.

[WD5JKO]

Dave,

   I'm not sure you read all of my post. Let me repeat what I said at the beginning,

"I agree with the others in that the Viking II will be easier to make decent AM than the HT-32."

I just went on to defend low level AM, which went unrepresented on this thread. Local to me, Yogi KC5MIP did some very simple mods to his HT-32, and I have to say that he sounds better with that rig then he ever did with his Globe King 500. Still low level AM presents more challenges to the new and inexperienced. That is why I voted with the group towards the Viking II.

Regards,
Jim
WD5JKO