If you mean the IF output, it is available on the backpanel of the R-390a. It is the BNC on the upper right as you are looking at the back.

Tony

@ Tony. Right. I know where it is. But will it work?
I'd like to run the IF out of the 390 to the 180AX to take advantage of better SSB. There's an HC-10 / SPC-10 hiding in the 180AX. I want to use it.
Can the IF out of the 390 be plugged into one of the crystal sockets on the 180AX with a made up jig of some sort?
There's an extra relay not stock to the 180AX that clicks when selecting the VFO or the crystals.


EDIT : Sorry, the relay is supposed to be there

The IF output would work. If you look at the HC-10 schematic and compare it to the 180A schematic, it should be clear where to tap into the signal path. It is in front of the mixer that downconverts to 60KHz. If that's where the crystal sockets are wired (probably not) then it would work. I am guessing that the crystal sockets provide a way to force the VFO to provide quick access to specific frequencies. Not what you need for this. I think you need to do some simple hacking to get it hooked up. Make sure that there is a DC blocking cap in the path somewhere.

Tony

Anyone know the difference in front panel nomenclature for the X model?

I see far more pictures of the X model with just HQ-180A on the front panel, and a few where it says HQ-180AX.
Also, there are variants of the crystal panel where some are grey, and some are black.
I have the black crystal panel with HQ-180A on the front.

Is there a way to tell if the X variant is stock? Was this addition available in kit form?

How about the IF silencer? Is there a way to tell if it's an addition, or came stock with it?
The IF silencer in mine does NOT have the plug in tube adapter, and is hardwired. Most of the wires are run down a hole in the chassis (same hole as the SSB/CW/AM switch wires), but the wires that go to the front panel knob are on top.
Also there is a bracket that's bolted to the side of the silencer that connects and bolts to the main radio chassis.

I got the installation manual for the silencer somewhere on the net. Might have been at http://www.hammarlund.org . It shows how it was installed, including the brackets. Unfortunately I only have a copy on my machine at work, or I would send it to you. Try that link and poke around. I think the document was called the "immunizer" or something like that.

Don't know anything about the X model variants.

Tony

edit: Yep it's there. Look under the "manuals" link.

I just put in the proper tubes in the 180AX. There were 2 6AU6s where 6BA6s should have been.
It blew one of the fuses (there's a fuse on each leg of the ac line with this one). The only other thing I did before firing it up was put some IERC shields where the original one were ( I got a smokin' deal. 24 shields for 24 bucks). I replaced the fuse, and brought it up slow on a isolated variac, checking amp draw. Nothing out of line there. Holding fine at 100V. Major beat note warble with the modulation peaks on SSB. Bring it up to 115 and SNAP. There was a spark flash right around where the big choke is, but I could see it flash on the top of the chassis. I rolled off the voltage to an immediate 0 and shut er down. No fuse blow this time.

I mentioned before that there is a burn mark on the chassis right above the choke where it appears to have been cooking when I received it.
Been playing fine and cool until I go and do a stupid thing like putting the proper tubes back in (duh.....) .
Why would putting the proper 6BA6s back in place of the wrong 6AU6s do this? Also I pulled the shields on the IF silencer. There's a 6DC6 where the 6BH6 should be too.

Subbing these 6BA6s for 6AU6s make it easier on an already teetering choke somehow?????

Maybe a carbon track. Clean the choke and area around the choke very good and try the radio again.

6BA6 and 6AU6 have identical pinout so there should be no issue. Sounds to me like an intermittent short or arc. I doubt that the shields or the tubes had anything to do with it.

Do the shields actually say IERC on the side or do they just look like IERC shields? Most of the black shields in my R-390a say WPM and seem to be made of lighter materials than the IERC. I have a few IERC in there as well.

Tony

@Tony http://www.ebay.com/itm/160769283224

Hmm, well something has obviously happened with the choke before. The chassis above it proves that.
This has been worked on before, quite a bit. But the work isn't ham fisted.

Never tested a choke before. Just go for an obvious ohm reading first?
Google here I come.

One of my HQ 170A's has the noise silencer option and the VHF converter option I do have a copy of the immunizer document on my PC. Not sure how to send it to you though. I find that I rarely use it since it seems to make the audio a bit scratchy on my receiver. In most cases, careful tuning of the slot (notch) filter really does the trick.

@ Tube Radio, Tony and others.

I removed the choke and cleaned the chassis, surrounding areas, and more or less prodded the whole under chassis with a medium stiff artists brush, and blew it all out. Put back the wrong tubes that were in it when I got it, and it's playing fine............

With a better look at the choke it was easier to tell where the flame up (or whatever it was) happened.

On one side of the choke where it's wrapped around the core, there is a very visible flame/shoot exit that hit the chassis at one point or another. My best guess is this may be where the previous owner drilled a hole in the chassis close by to mount the extra support framework, and maybe some metal shavings got in there? Looks like it was a pretty forceful exit whatever escaped the choke.

Anyways, here it is about an hour later, and when I put my hand on the chassis directly where the choke is bolted, it's barely warm to the touch. I fact any warmth I feel in the area is probably from the surrounding tubes.

So... wrong tubes, and working. Must be a mod or SOME kind of reasoning to sub 2 6BA6s with 6AU6s.

I plan on taking the mil spec 6DC6 out of the IF silencer (why is THAT in there??!!!) where a 6BH6 is supposed to be, and saving it for the 390, as IT'S 6DC6 has been subbed with yet something else!!

Oh, and since this has a fuse on each leg of the AC line, what's the safe fuse rating to use? I received it with a 2A on one leg, and a 3A on the other.

Fusing both sides of the line is not good. Does it have a 2 wire or 3 wire cord now? Preferable is to switch to a 3 wire grounded cord if that is not already the case. A 2 amp fuse will be fine but it should be in the hot (load) side of the line and the neutral side should NEVER be fused. If you want to stay with an original two conductor plug it is best to mark one side as neutral and conscientiously keep it plugged in that way (make sure the outlet is also wired properly). Put the proper fuse in the hot side and short across the fuse holder that is in the neutral side. A variation of this for keeping the original two fuse plug (common on early Johnson and Heathkit gear) is to use a properly sized fuse in the hot side and then using a 20 or 30 amp "slow blow" in the neutral side to make sure it isn't the one that blows.

Worst case is when a neutral fuse opens and the receiver is not grounded. Because neutral is tied to ground at the service entrance, if a fuse in the neutral side opens but a fault causes the chassis to become "hot" then touching the receiver and another grounded piece of equipment causes your body to become the new neutral conductor. The old safety adage for ham gear is that ground should be the first connection made to a piece of gear and the last to be removed.

Rodger WQ9E

It is the 3 wire type. This thing has me all sorts of confuzled. Extra framework, tube subs, R-390A case, all mil spec tubes, and both legs of the AC fuzed. Blows fuzes and sparks with the correct tubes, but works with the wrong ones, nicely.

Got a guy in the air on phone patch telling his wife on the ground that he loves her and all that on 11175 at the moment.

Guess I'll just leave it be!

The arcing will be back. There's no way that a swap between 6AU6's and 6BA6's should do that. If the arcing really is correlated to the tube swap, and not just coincidence, then something else is messed up. You saw the black marks there when you got it which suggests that it was arcing when the 6Au6's were in there too. Arcing in a choke sounds to me like inductive kick which could be caused by the coil going open or a loose connection from the choke to the circuit or a short that comes and goes.

As for the 6BH6/6DC6 sub, this is the opposite situation where a sharp cutoff tube has been replaced by a remote cutoff tube, not necessarily a bad thing. The 6DC6 has very different specs from the 6BH6. The 6BH6 has a Mu of 6600 while the 6DC6 is 2700. I don't like this sub either on the face of it.


That arcing would scare the whatever out of me until I figured it out and fixed it.

Tony

Really the only thing I can think of would be I cleaned a laundry marker off the chassis with steel wool (another thread on that altogether) and maybe some of the metal 'dust' got in where it shouldn't have. I was careful to mask off everything, but who knows.

I blew out, and stiff brushed off the tube sockets, and choke (I removed it to clean it). Maybe the right tubes would work after all that cleaning, but for the moment I'm happy it's not popping fuses or arcing.

Should the area that the choke is bolted to be hot, warm, cold?

It's slightly warm, but nothing to suggest that its running hot enough to cause the bake mark that's there from a previous owner.

Update. I ordered some mil spec 6BH6s and put one in the IF silencer where it should go (there was a 6DC6 there). Put the 6BA6s where they should go (there were 2 subbed with 6AU6s). Running fine this time. With the 6BH6 back in the silencer, the control knob makes it respond less than it did with the 6DC6 in there. Oh well. Proper tubes back in, no smoke. No hum (my other 180A buzzes and hums even after the electrolytic replacements). After an alignment (band 1 is really off, all others are very close to perfect) I'll call this one good.

I'll have to chalk the arcing up to a shorted 12AU7 variant that turned up.

Time to dig into this oddball 180. It's been playing reliably for a couple weeks now, but all of a sudden, it started making the isolated variac I have buzz like crazy. I checked to see if it was a problem with the iso-vac by turning off the 180, and plugging the r-390a into it. No buzz from the iso-vac. 180 made it do it again. Guess I'll start with the 80-40-20uF@450 cap in there. No hum to the speaker at all though, but a very audiable buzz from the iso-vac that only the 180 causes.
Hmmm.

Here's a picture of one just like mine