Argonaut 505

Like I need ANOTHER ham radio project to work on...

Last year at WASHFest, my friend Bill W3WH bought a Ten Tec Argonaut 505, with the accesory CW filter. Bill was told that the unit was working just fine.

It wasn't. No receiv. From what Bill said, it sounds like the "90197 RF Front End Board" may be shot.A trip to Sevierville revealed that it has some major audio problems (exactly what I don't know yet) and was unrepairable by the factory; combination of some parts no longer available, and the cost to repair would well exceed the value of the rig.

Bill had it on our table at WASHFest this year. And we ended up swapping for it, as I had a few things he wanted. Well, if nothing else, it will look nice on the shelf next to the TT PM-2B, the Ameco AC-1, and some of the other little QRP rigs I've collected recently.

Suffice to say, if anyone has a 505 out there that they're parting out, sooner or later, I do want to talk about possibly obtaining that board, possibly other parts as well.

Just curious, do they give any indication of what was wrong other than just generalizing?

I'm sure they told Bill. He couldn't remember the details, and he was going to find the paperwork.

Let me know what you need in the way of parts. I may very well have them.

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Originally Posted by N8YX

Let me know what you need in the way of parts. I may very well have them.

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No problem. I just need time to look at the schematics and do some basic trouble shooting.

I didn't see you, so I'm presuming you guys didn't make it down. Pity, we had a good show. Our two big commercial vendors, plus the local lady who does the embroidery, have already committed to their tables for next year... so we've already presold 23 out of 70 tables!

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Originally Posted by W3WN

No problem. I just need time to look at the schematics and do some basic trouble shooting.

I didn't see you, so I'm presuming you guys didn't make it down. Pity, we had a good show. Our two big commercial vendors, plus the local lady who does the embroidery, have already committed to their tables for next year... so we've already presold 23 out of 70 tables!

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Nope - didn't make it. 'DSG had a rather harrowing drive back from her mother's place on Saturday evening and was tripped out as a result. We'll be at Breezeshooters, though.

Yeah, I saw the weather forecast Friday night, and the news reports on some of the whiteouts up by I-80. We were sweating bullets on that through Saturday night...

According to the schematics:


Of course, there's no diagram (in the downloaded copy) of the RF Front End Board.

Transistors on some of the other boards:

90195 RF Power Output Board:
Q1, Q2: 2N2631

90184 IF Board:
Q1 2N5134
Q2 40823
Q3 2N5133
Q4 2N5134
Q5 2N5133
Q6 2N5134
Q7 2N5134

90186 Audio Power Amp board:
Q1 2N5139
Q2 2N5133
Q3 2N5128
Q4 2N4105
Q6 2N5134

Oscillator Sub-Assembly:
Q1 2N5128
Q2 2N5134
Q3 2N5134
Q4 2N5134

A lot of these transistors are used throughout.

Let me know which, if any of these, you have (or equivalent substitute). And I'll sit down next day or three and go through the manual to see what other ones the unit needs. I'm not too worried about diodes, caps, and resistors, but these will be the critical components (famous last words)

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Originally Posted by W3WN

Yeah, I saw the weather forecast Friday night, and the news reports on some of the whiteouts up by I-80. We were sweating bullets on that through Saturday night...

According to the schematics:


Of course, there's no diagram (in the downloaded copy) of the RF Front End Board.

Transistors on some of the other boards:

90195 RF Power Output Board:
Q1, Q2: 2N2631

90184 IF Board:
Q1 2N5134
Q2 40823
Q3 2N5133
Q4 2N5134
Q5 2N5133
Q6 2N5134
Q7 2N5134

90186 Audio Power Amp board:
Q1 2N5139
Q2 2N5133
Q3 2N5128
Q4 2N4105
Q6 2N5134

Oscillator Sub-Assembly:
Q1 2N5128
Q2 2N5134
Q3 2N5134
Q4 2N5134

A lot of these transistors are used throughout.

Let me know which, if any of these, you have (or equivalent substitute). And I'll sit down next day or three and go through the manual to see what other ones the unit needs. I'm not too worried about diodes, caps, and resistors, but these will be the critical components (famous last words)

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Lookie here:

http://www.ebay.com/itm/2N5139-Transistor-x-1-pieces-/150583576631?pt=LH_DefaultDomain_0&hash=item230f7b 0837

http://www.ebay.com/itm/2N5134-Trans...item230f7b07eb

http://www.ebay.com/itm/PCK-10-2N513...item5ae363f212

http://www.ebay.com/itm/2N5128-npn-t...item2318b12bf6

http://www.circuitspecialists.com/mps5128.html

http://www.smallbearelec.com/Detail.bok?no=492

http://www.talonix.com/shop/item.aspx?itemid=3389

http://www.circuitspecialists.com/mps5139.html

http://www.alltronics.com/cgi-bin/ca...ry=63&start=36

Well, I caught a small break. Bill can't find the paperwork he got back from Ten-Tec, but he posted a query to the Ten Tec reflector last March. The 2N4105 & 2N4106 transistors in the audio power amp need replaced. Alltronics for one has them. So I'm going to check and see how many I need and order them (plus a few extra, just in case) right after payday.

One step at a time. I just hope the finals aren't shot, it appears that the originals (2N2631) and their replacements (2N3553) are now made out of Unobtanium.

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Originally Posted by W3WN

One step at a time. I just hope the finals aren't shot, it appears that the originals (2N2631) and their replacements (2N3553) are now made out of Unobtanium.

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I would redesign the PA and look at using an MRF device or its equivalent. Have a look at an NTE236 for starters, or a 2SC1969.

Nice rig! I hope you get it working.

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Originally Posted by N8YX

I would redesign the PA and look at using an MRF device or its equivalent. Have a look at an NTE236 for starters, or a 2SC1969.

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Well, if it gets that far... but first things first.

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Originally Posted by N8YX

I would redesign the PA and look at using an MRF device or its equivalent. Have a look at an NTE236 for starters, or a 2SC1969.

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I like the MRF458 for HF amps. They are very stable and easily matched. No coupling or feedback issues. Just a good solid performer. My wife closed out all the RF transistors they had down there. I got them for their cost at the time they bought them. Somewhere in the 80s. Bless her heart. There were a lot of MRF245 80w @ 136-176Mhz. And a bunch of low power, med pwr, hi pwr from below 2Mhz up past 500Mhz and some in the micro wave region. Already fixed and sold a bunch of radios, but I have many more to go.

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Originally Posted by K7SGJ

I like the MRF458 for HF amps. They are very stable and easily matched. No coupling or feedback issues. Just a good solid performer. My wife closed out all the RF transistors they had down there. I got them for their cost at the time they bought them. Somewhere in the 80s. Bless her heart. There were a lot of MRF245 80w @ 136-176Mhz. And a bunch of low power, med pwr, hi pwr from below 2Mhz up past 500Mhz and some in the micro wave region. Already fixed and sold a bunch of radios, but I have many more to go.

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Well, IF I get to the point that I have to revamp or redesign the PA, I will be talking to you and Fred. I'd probably want to boost the output from 5 W to 10 W or so too... but first things first.

That receiver has to be brought back to life, or the rest of the rig is a moot point.

You could always put a 5 tube ac/dc Silvertone ahead of it.

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Originally Posted by K7SGJ

You could always put a 5 tube ac/dc Silvertone ahead of it.

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Hah! :twisted:

An All American 5, naturally!

Besides, I still have my OTHER project rig... the Swan 3Drifty, er, 350 station. That would do as well.

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Originally Posted by W3WN

Hah! :twisted:

An All American 5, naturally!

Besides, I still have my OTHER project rig... the Swan 3Drifty, er, 350 station. That would do as well.

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Maybe you can get it to drift close enough to merge. Then you would probably end up with a Swargonaut 3505, eh?

Boy, has it been almost 6 months already?

Came across a ham on the Ten-Tec reflector with time on his hands, test equipment, and looking for projects to work on. He offered to take a look at the Argonaut, so it's in his hands right now.

Keep your fingers crossed! (NO, not THOSE fingers!!)

And I've sent him the links you gave me Fred, since at least one (Alltronics) appears to have the appropriate transistors in stock for the audio board.

It doesn't look like I got around to posting this before, but I heard back from John Henry at Ten-Tec. The audio power out transistors (2N4105 & 2N4106) appear to be shot. They didn't bother troubleshooting beyond that... TT no longer has those transistors in stock (well, the rig is around 35 -40 years old!!), so they stopped there, they don't believe in running the charges up. But first things first.

And as I said before, if the finals are shot, which would be a redesign, going from 2-3 W out to about 5 to 10 would make some sense. We'll see.

Do keep us posted. I for one am curious. Oh....wait.. that's on Mars.....oh well, keep us in the loop.

I've heard back from Wade.

The new transistors arrived yesterday. Along with new grease for the PTO -- the old had hardened, a common issue. The PTO is now mechanically functioning again. He removed the old transistors, removed them from their heat sinks, and got the new ones installed.

In the process of the removal, he accidentally drilled himself in the finger... seems that because of the short lead lengths, he had to drill out the heat sinks... so the rig has drawn first blood.

Should know more later today or tonight.

Any time a rig gets a blood sacrifice it'll end up working peachy. Or so I suspect.

Well, there is a strong reason to finally get cracking on that FT-902DM I have. I did cut myself a little inside the case a couple of years ago. :lol:

I have a bunch of spare pieces for the 90x series too. Let me know what you need.

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Originally Posted by N8YX

I have a bunch of spare pieces for the 90x series too. Let me know what you need.

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Sounds like he needs a bandaid.

Word tonight is that the audio board is functioning again. The 505 is somewhat deaf at the moment, but at least once it gets a signal, it's processing it.

I'm concerned about the rig being deaf, but not for the reason you might think. Ten Tec made an external audio CW filter for the 509, and there was a mod to the 505 so that the filter would work on it as well. Well, this 505 has (had) the mod... and I forgot to send the filter along with the radio (it got buried under some other stuff). Well, if Wade needs it, off it goes.

But I'm feeling hopeful.

On Edit: The rig's not deaf. After I mentioned to him that I'd neglected to send the filter, he checked, found where the jumper should have gone, and voila! it hears just fine.

Schmuck. (That's me) I should know better... fortunately, no harm done.

I think I'll let Wade speak for himself:

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Transmit problem was a combination of, a loose connection on 80 Meters and a Dirty Band Switch.

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It's working! Just needs some DeOxit on the band switch, and it's ready to come home!

http://pull.imgfave.netdna-cdn.com/i...911269441.jpeg

Received an email from Wade a short time ago.

The 505 has passed all tests with flying colors, and he even made a few QSOs with it this afternoon.

It's being sent home first thing in the morning.

After it arrives, we're just going to have to set up a few skeds...

So I walk in the house after work, and the boss gives me a cross-eyed look... uh oh... and asks me...

"What's in the box?"

As soon as I see KJ4WS on the return address label, I relaxed.

Yes, the 505 is home.

No, I haven't fired it up yet. I spent the rest of evening daylight working on the front deck, and I have a few other things to take care of. BUT, I took Friday off. Officially to work on the deck...

Anyone going to be around on Friday? Remember, this rig doesn't have WARC bands...

Ron, looks like KJ4WS did a good job on that Argonaut 505. I just used it for the first time and worked JA1QS SSB phone—on 10m.

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Originally Posted by KJ6BSO

Ron, looks like KJ4WS did a good job on that Argonaut 505. I just used it for the first time and worked JA1QS SSB phone—on 10m.

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I'll let him know.

And it's a relief to know it survived the shipping. You never know these days, no matter how well you try to pack things...

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Originally Posted by W3WN

I'll let him know.

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Tell him this, too: My first QSO worked out to 1133.9 miles/watt, and on 10m no less. I think I could learn to like this QRP thing...

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And it's a relief to know it survived the shipping. You never know these days, no matter how well you try to pack things...

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Yeah, no kidding, but I've had much better luck with the USPS in that respect than either UPS or FedEx. I now ship with the postal service almost exclusively.

And now add CE3CT, also SSB phone on 10m. Only 1094 miles/watt, though.

I'm having a blast with this thing. I don't make a lot of DX QSOs but each one I do make feels like a real accomplishment.

Cool. You have it hooked up to a nice speaker? How's that RX audio sound? :)

I worked Croatia a bit ago on 12.

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Originally Posted by WØTKX

Cool. You have it hooked up to a nice speaker? How's that RX audio sound? :)

I worked Croatia a bit ago on 12.

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I unplugged the speaker from my currently non-functional TR-7 and am using it with the Argonaut. The audio is quite good and I found the #2 CW filter to helpful on SSB during contest conditions.

Croatia is a good one. Alas, the Ten Tec rig does not do the WARC bands.

Okay, now add ZM1A, Waihi Beach, New Zealand. 1304 miles/watt.