SO I got this FT-101E the other day...

[VA3CQC]

...and it doesn't work. =(
I'll show you pictures of it here: http://mgear.imgur.com/ft101e

Fired it up and the tubes glow, but one of them looks like it flashed over somehow. The PA tubes are shiny where they should be clear, and blackened inside. It looks like something came out those three little "ports" on the side of the plate and scorched the glass. Bizarre, and the driver tube looks fine. I checked its receive and it seems to work allright at least on 80/40/20. I got new tubes from a ham friend of mine, and socketed them in. The heater works and I have set the bias to .06amps, but then the Ic doesn't rise as I turn up the Carrier control. (I thought at first I was crazy but then, I know I'm doin it right because I have a 101ZD that I use every other day, so I'm not half bad at doing the drive-plate-load dance) I was preparing to try to neutralize, so I was attempting to tune up on 29mhz, tried both 10B and 10C, and their respective dial positions both land right on 29mhz! I listened with another radio (connected to a dummyload, with its attenuator on...) and I can hear carrier/my voice if I key the 101E, but the wattmeter, even on its lowest setting shows no power.

My question is, where would you suggest going from here? I've had some suggestions so far:

Check the power supply voltages (at the power supply section or the tube socket?)
Try tuning up on the lower HF bands (like 80/40) because supposedly neutralization isn't needed

[AB8RU]

I found on a auction site a copy of the FT 101 manuals and I bought one I own a FT101 EX and it showed the problem.

the 15 volt lamps are odd voltage and I went to Radio Shack and bought the replacement lamps.

As to your vaccum tube issue I would sugguest finding someone or purchasing a USED vaccum tube tester make sure it will handle the one you need to test.

I also acquired from a family member who was an Electronics Engineer some tube manuals, what I did on occasion was to subsitute a item and compared heater voltages, and it did fairly well give some readings.

In some instances the typed out manual only gave some were for household appliances. Now with the internet there is sites with data.

[VA3CQC]

I've gone through the service manual (it's something like 200 pages!) and it doesn't say anything specific about my problem, just "this is how you perform X". If I knew it was Alignment, or Neutralizing, or whatever service procedure then I could look it up in the book. I have idle current drive, but it doesn't rise properly with the front panel control, I have a working exciter as it does transmit, albeit weakly. Where do I go from here?

I suppose I could get a multimeter and see if at least the knob's potentiometer is broken... I've just been so busy lately, had no time to even put it up on the desk. =(

[KB4QAA]

I assume the manual has a diagram with voltages. Have you gone through that yet?

[VA3CQC]

That's my next step, I just haven't had time recently to work on the rig unfortunately.

[KC8VWM]

Sometimes the plug in boards need to be removed and the contacts cleaned with a pencil eraser. Sounds to me like a circuit isn't functioning properly. It doesn't hurt to do this anyways and it's good maintenance for the rig.

Just a tip, but before checking any of the tube socket voltages, you always want to confirm the B+ or filament voltages are good from the power supply section first.

Somewhere in that 200 page encyclopedia, it probably also indicates voltage test points that may be useful to check and might help to "isolate" the area of the problem.

However the description of the previous tubes seems to indicate there may be other components to check first. Did you sniff around to see if there are any open resistors, does it look like anyone had a BBQ party anywhere under the chassis etc? Does it smell like someone left a T bone on the grill too long, or does it have a normal sweet plastic chemical smell? I think I would start a sensory investigation first before breaking out the test equiqment and hopefully the one you got didn't live it's life communicating on the logistic transportation engineer band.

[WD0GOF]

...and it doesn't work. =(
I'll show you pictures of it here: http://mgear.imgur.com/ft101e

Fired it up and the tubes glow, but one of them looks like it flashed over somehow. The PA tubes are shiny where they should be clear, and blackened inside. It looks like something came out those three little "ports" on the side of the plate and scorched the glass. Bizarre, and the driver tube looks fine. I checked its receive and it seems to work allright at least on 80/40/20. I got new tubes from a ham friend of mine, and socketed them in. The heater works and I have set the bias to .06amps, but then the Ic doesn't rise as I turn up the Carrier control. (I thought at first I was crazy but then, I know I'm doin it right because I have a 101ZD that I use every other day, so I'm not half bad at doing the drive-plate-load dance) I was preparing to try to neutralize, so I was attempting to tune up on 29mhz, tried both 10B and 10C, and their respective dial positions both land right on 29mhz! I listened with another radio (connected to a dummyload, with its attenuator on...) and I can hear carrier/my voice if I key the 101E, but the wattmeter, even on its lowest setting shows no power.

My question is, where would you suggest going from here? I've had some suggestions so far:

Check the power supply voltages (at the power supply section or the tube socket?)
Try tuning up on the lower HF bands (like 80/40) because supposedly neutralization isn't needed


The repair and maintenance of radio equipment requires a broad spectrum of technical skills. I would suggest, go to a local Ham club and find a mentor to help you develope the skills and knowledge needed. Or take one of the many online radio repair and theory courses. Learning on the fly turnes a lot of good rigs into parts rigs.

73, Good luck

[VA3CQC]

Sometimes the plug in boards need to be removed and the contacts cleaned with a pencil eraser.
...
Did you sniff around to see if there are any open resistors, does it look like anyone had a BBQ party anywhere under the chassis etc?
...
Hopefully the one you got didn't live it's life communicating on the logistic transportation engineer band.

Good call! I think I will try to get at removable stuff and clean their contacts. Do you know any way of cleaning up a bad potentiometer? Is air duster a good call, or something more like terminal cleaner (methyl alcohol)?

I've heard of one such mica cap that goes bad, and resistors under the tube sockets. Nothing (save for the Plate-tuning capacitor: http://imgur.com/GivDW.jpg and http://imgur.com/CbzFR.jpg It's got these scorch-marks that look like it flashed over at some point. I NEVER saw sparks from that area when it was on.) looks burnt up or broken or out-of-the-ordinary. It doesn't smell like anything other than burning dust, same as a lightbulb you haven't used in a week or two, and even that I think got burnt off because it doesn't smell at all now!

I'm really, REALLY gonna try to work on this thing this weekend. Here's hoping! Thanks all you guys!

[KC8VWM]

The photos of the black marks on the tuning capacitor plates looks to me like someone didn't really know how to tune up the rig properly.

Incorrectly loading the capacitor plates would probably also explain why the tube went kaput too.

The reason why your potentiometers are "scratchy" is because the rig has been unused in storage. This causes the internal wiper contacts to oxidize resulting in poor or "scratchy" connections.

The fix is simple - use the controls.

It's not necessary to use "cleaner" on them. In fact, some of these so called contact cleaners will actually do more harm than good. The oils in some of these cleaners are intended to function as lubricants, but similar to the gulf oil spill, it will reside on the shores inside the control forever while continuing to attract and hold onto surrounding dirt, dust and debris very well for a very long time. So now what you end up with is oil nside the control serving as a conduit to attract and hold even more dust and dirt which only serves to compound the problems you intended to fix. So, incorrectly stating that oil in contact cleaner is somehow going to work and function as a "cleaner," Um.. no.., it is not. Well enough of my babbling ranting and let's get back to the problem.

I would just work the controls back and forth in full rotation about 100 times is all you need to do to "clean" them. This action cleans and restores the oxidized wipers inside the potentiometer back to new. Think about it like you are "rubbing" them clean.

Next problem.. Oh yes, the smell of dusty tubes. Ahhh..I love that smell lol

When sniffing around for a BBQ party you weren't invited to inside the rig, you want to make sure the rig is turned off because the smell of tubes will mask any other detectable smells or problems. You want to smell around for problems inside the rig only when the rig is stone cold, and only after you stuck your nose in the freezer for 5 minutes to properly calibrate it first. :) Ok, I'm just kidding about the nose in the freezer part. :p

Keep us updated. In fact, I have an FT 101E I am looking at in front of me right now.

[VA3CQC]

The repair and maintenance of radio equipment requires a broad spectrum of technical skills. I would suggest, go to a local Ham club and find a mentor to help you develope the skills and knowledge needed. Or take one of the many online radio repair and theory courses. Learning on the fly turnes a lot of good rigs into parts rigs.
73, Good luck

I would, trust me! My ham club meetings don't start for another TWO WEEKS! T_T

I'd be scared to death of opening up my functioning 101ZD, but I was offered this 101E sight unseen, I didn't expect it to work. When I saw it was in good condition (if a little mouldy-basement-smelling), I was thrilled even for the opportunity to receive on it! It'll be a project-radio, a learning experience even if I can't goad more power out of it, and (knock on a vacuum tube) if my ZD ever bites it I'll at least know where to start looking for problems.



...hopefully the one you got didn't live it's life communicating on the logistic transportation engineer band.

Well..... ahhh.....*ahem* It DOES have a crystal in the AUX spot, but I've no way to verify what it is for, there's no markings on it. I've heard that the blackened tubes are caused by people trying to run 100watt AM carriers because they think the rig is capable of it.

[VA3CQC]

The photos of the black marks on the tuning capacitor plates looks to me like someone didn't really know how to tune up the rig properly.

Incorrectly loading the capacitor plates would probably also explain why the tube went kaput too.

Yes, that was my thought as well. Someone didn't know how to tune it up. I got it with an antenna tuner (it is ABSOLUTE TRASH, but I'll come back to that...) and they both look well-used, I never knew the original owner or even who he was. Can I..... should I....... IS IT EVEN POSSIBLE to clean that junk off?

I didn't say the pots were dirty, I'm just afraid the Carrier pot has failed. Trying to determine what to do if that is the case. The volume control, and all others are nice and smooth, no scratchyness!

I tried to use the tuner (it's a KW107 'Supermatch', some sort of wierd balanced-line tuner with only two inductor steps) and I found it unable to match anything! Even worse, it was affected by hand-capacitance! The knobs are even mounted on long shafts presumably to prevent this, but my hand on the knob either tunes or de-tunes it, and if you actually go and turn the knob, there's a scratchyness like a dirty pot, and it's SUPER loud. Makes it difficult to tune up while listening to something for you to peak the receive on which is what I do to reduce some tuneup-QRM. So after trying a bunch of times on different antennas, I cracked it open to "find out why", and the transmitter-matching cap has the wierdest look I've EVER seen. Like that plate cap above, but a hundred times worse! It looks like it was stored in a vat of salt water! Totally corroded-looking, all the plates have this black crud all over them! But get this! The other cap, the antenna-matching cap, looks brand-spanking-new. I can see the reflection of my face in the plates it is so clean. I'd take pictures, but when I saw that, I closed it up and it went DIRECTLY into my "for sale" bin. Is that any clue as to what happened to this thing before I got my hands on it?

[KC8VWM]

It occured to me after looking at mine that it's required to have the ACC plug installed in the back of the rig for tx'ing.

It's just a thought but jumping pins #1 and #2 on the ACC plug socket (blue wires) will provide power to the 6JS6C tubes thus enabling the rig to TX.

Sometimes, logistic transportation engineers remove these plugs from the sockets and loose them in another box somewhere.

Kinda what I had to do to get mine to TX. :o I might be wrong but let's see if that's the case with yours first:

To make your own jumper use a metric tape measure and cut exactly 15 mm of #12 copper wire and strip off 2mm of covering off the end.

lol.. of course, it doesn't matter how the heck you make the jumper wire so long as it's there.


http://i629.photobucket.com/albums/uu18/kc8vwm/MVC-009F-1.jpg

http://i629.photobucket.com/albums/uu18/kc8vwm/MVC-012F-1.jpg


KC8VWM's FT-101E :)

http://i629.photobucket.com/albums/uu18/kc8vwm/MVC-011F-1.jpg

[VA3CQC]

Yours actually has the 11meter position! Mine has instead AUX in between "10D" and "WWV".

The ACC plug is present on the back of my 101E, my 101ZD has the little snippet of wire, BUT IT WASNT INSULATED!!! Argh, I grazed it once with my pinky finger accidentally while trying to adjust something (PO meter or ANTI-VOX or some crap), all I remember is my arm flying up and me screaming "WHAT IN THE F*%&$ WAS THAT?!?!?!?" I didn't think anything was live back there w/o the key down, I was new.

Mine actually DOES transmit, but from the exciter stage, NOT the PA stage. So there is no rising grid current, no discernible TX power on a wattmeter, ALC moves like it should, and you can hear it! It's very weak, not even 1 watt I would say. It's freaky though because the PA controls don't "do" anything, but it is transmitting! I can pick a frequency and it is right there.

I think I posted the link to mine: http://mgear.imgur.com/ft101e/

[KC8VWM]

I would probobly make sure the tubes you have are in fact working. A tube checker would be helpful, but there are ways you can check it with a multimeter too if you get a copy of the tube data sheet and study it carefully.

The problem sounds like a it's a simple fix really. Have you checked the relays? Are they engaging (electrically) during TX? You might consider cleaning them anyways. One way to do this is by sliding a dollar bill (not a looney coin - but Canadian Tire money might work) :D soaked with a little isopropynyl and "scrub" it back and forth across the relay contacts.

Other things I would look for are open resistors and blown chokes in and around the PA stage. (L4-R9 etc.) R14 (100 ohm) looks like a potential candidate to check first. That resistor is fed by an orange wire which should power the PA. This is assuming the relays are functioning correctly to energize the whole sequence of events to take place etc. If C13 is leaky it may destroy the tubes too. It should be an 60pf 1kv cap and may be worthy of replacement especially if the rig was mistuned quite a bit, the guy probobly smoked it.

[VA3CQC]

The tubes pictured are the ones that came out of the rig. I've since gotten new 6JS6C's and driver, though I think the old driver is good. The tubes were verified at 75% and 80% on a Military-style Tube Tester before I bought them.

I'll add to my list of things to check: the operation of the T/R relay(s). You're right, if it's a multi-contact relay maybe the exciter-relevant contact is closing but not the PA-relevant contact.

I'm going to open it up most likely tonight, or failing that I'm lugging it to work tomorrow and working on it there! Hopefully I can post some pictures in more detail of what I find. I'm sorry if I come off as assuming you know things about this rig, I've been posting this story everywhere and asking any ham I come across, so I forget how much I've explained sometimes.

[KC8VWM]

Ok I'l come back later to check on ya...

[KC8VWM]

After looking at the service manual tonight (because your thread re sparked my interest in looking over my own FT101 for something to do:)) During my reading I found out, it might be worthwhile to check and replace C17.

It appears if this capacitor is leaky, it causes final bias voltage to be fed into the ALC circuit and produces a low RF output condition almost exactly as your have described.

The service manual also indicates replacing this capacitor should restore normal output power.

Interesting... I might replace C17 in mine, just to prevent this problem from occuring.

[VA3CQC]

What page references this? I'll take a look into it for sure!

[KC8VWM]

See page 4-8 section called "Low or no transmitter output" which describes the condition and the cause.

Also see page 4-11 section called "Low output on al bands."

[VA3CQC]

Thanks very much!

[VA3CQC]

Mmmkay... After sitting on this thing for, oh, close to a month, I opened it finally to have a look. The first thing I noticed that under these fluorescent lights at my work, the thing looks filthy! So at once I cleaned the CRAP outta it, removed some of the knobs and cleaned them (mainly volume, plate and load), also especially the VFO knob, it was wiggly but I tighened it up and sprayed WD40 on the gears while it was open. Butter-smooth tuning now, no "rough spots".

I also noticed that "funky mylar" post, and mine has that stuff on it too! I tore 99% of it off, and then dinged the case getting the final 1% off. >_< It's only a small scratch, can't even see it.

Then, when all the cleaning stuff dried, I took it apart and got one hand on the voltmeter, other hand in my pocket. Checked all the low voltages, 120v is reading 119v, my line volts are set to "115" and they are actually at about 119 volts. My multimeter (and the radio) freaked out when I went to measure the 400+ and 600+ volts rail, so I skipped those for now. I will assume some high-enough voltage flowed through the meter.

On TX the idle was still low, actually at zero. But I twiddled the BIAS.ADJ pot and got the idle current up, then I went with the normal tuning procedure and lo and behold it produces power! Lots of it! But it doesn't want to go on 20 meters, and I get nothing if I try for higher bands. I think it also might need neutralization because I saw a "slow dip" on one side of the PLATE control, and a "fast dip" on the other when tuning up on 40. Not so much on 80, in fact it acted quite normal on 80.

I'm an idiot though for not bringing a power meter of some sort. I coulda measured the input watts even, but didn't think to bring anything but a wire and a dummy load, I honestly didn't think it was gonna go. It produced some power, but I don't know how much.

Yay! This is a start. Next I gotta crack the bottom open, get out my "plastic screwdriver" and try to neutralize!

[VA3CQC]

EXCELLENT, ABSOLUTELY EXCELLENT NEWS!

It's alive and well on at least four bands! At first glance on the wattmeter, it's generating almost 30 watts! I didn't change the settings from when I tried it at work.

But then, I grabbed the first HF receiver I could find and tuned up on every band it had! Starting on the top band, I found it generates full output on 160, 80, 40, and 20 meters. 30 meters is receive-only on this rig as it was WWV at the time and not 30 meters yet. Tweaked the neutralizing cap so the rise in grid current is about equal on either "side" of the dip.

I COULD NOT generate any power on 15meters, or 10meters, any dial position. (AUX slot has no xtal, therefore it was never used on 11m) Tried high, tried low on the band, nothing. Interestingly, the CARRIER control does not raise the grid current like it should. I only get a slight, ever so small twitch of the meter, and I can't even SEE that thing dip if there is a dip with the plate control. No power output.

To get the grid current up the PRESELECT only needs to me moved by a hair, so the T/R allignment is decent. Tried calling CQ but no reply. I can't wait to get this thing on the air. I gotta update my photos, it looks so different now that it's not all filthy.

[W5RKL]

The Grid current meter position displays the level of final tube grid current when adjusting the drive control. The level of final tube Grid current depends on the level of RF from the driver.

Have you checked the 15 and 10 meter heterodyne crystals to see if they are oscillating? You can do this by listening on a separate receiver tuned to the crystal frequency.

73s
Mike

[VA3CQC]

You mean I should listen on 27.02mhz for the 15meter XTAL signal? (it'd be 34.02/34.52/35.02/35.52 for 10m) Where would I listen for it? Just in the near vicinity of the radio, or on the PL259 output connector, also is it "live" all the time or only on TX?

Just to clarify, I have the preselect set for max rc'd signal (was using the xtal calibrator to ensure this) but when I go to raise the Ic from the bias level it only goes up a TINY bit, like 1mm, even at full CARRIER, and the deflection from turning the plate can't be noticed. I'm not sure if it produces an audible tone on a receiver (I have checked before, but I don't remember what band, so it might have been one of the working bands).

I'll try this at the next available opportunity, thanks!

[KC9QQM]

Just to jump in here with congrats you have it working. I just picked up a 101E at a hamfest about 10 days ago. Been interesting following this thread. I don't have a tuner or a tuinable antenna so trnasmitting is out of the question for now but it is a good learning experience for me also!

Keep us posted!

73
Jeff
KC9QQM

[VA3CQC]

Keep us posted!

Heh heh heh... you asked for it!

[VA3CQC]

Ok well since IMGUR hates me right now, Picasa Web Albums it is!

http://picasaweb.google.com/n95gear/FT101E2?authkey=Gv1sRgCLqkxtODuqXI5gE&feat=directlink

I hope the link works, this thing looks beautiful! I got a nice shot of the preselect-thing. Actually I should learn how to work the auto-focus on my camera, DURR. Half of those shots are blurry but it's not like you can tell on the tiny preview screen. =( Tell me what you think, the old pics (of when I got it, all dirty) are here:http://mgear.imgur.com/ft101e

Next step, get on the air! =)

[KC9QQM]

WOW I can't believe how clean yours is. I cleaned my case, took the front and all knobs off and cleaned/scrubbed. Inside well I blew it out and removed all the cards and cleaned their connectors but it still looks like an old radio!

What I need next is that same tuner!

Jeff
KC9QQM

[VA3CQC]

The tuner is just for show actually. One such as that has no switch, and so is hard to use with a tube rig, assuming you tune up off the air like I do. My MFJ versa2 is the one I usually use with this, but it doesn't fit so nicely on top.

I spent about 3 hours cleaning it last saturday. I guess the face is clean because of the "funky mylar" that was on there. I didn't pull the boards per se, just kinda hosed them off with an air duster. Q-tip fulla Superclean for the bad spots.

Glad you like it!

[W5RKL]

You mean I should listen on 27.02mhz for the 15meter XTAL signal? (it'd be 34.02/34.52/35.02/35.52 for 10m) Where would I listen for it? Just in the near vicinity of the radio, or on the PL259 output connector, also is it "live" all the time or only on TX?


Yes.

Connect a piece of wire to the separate receiver's antenna connector and the other end placed close to the FT-101's "PB-1073" board. Wrap tape around the end placed close to the FT-101's "PB-1073" board so the wire doesn't short to the 101 board. Use "insulated" wire.

Set the FT-101E to 15 meters and tune the separate receiver to the 15 meter band's het osc crystal's frequency (27.020Mhz). Do this with all three of the 10 meter band switch settings as well. If the any of the crystals are working you will hear the osc signal in the separate receiver. This is an easy way to tell whether the crystals are oscillating or not.

The oscillator is "Live", as you say, as long as the FT-101 is powered on. The band switch changes the individual heterodyne oscillator crystals.


73s
Mike

[VA3CQC]

Connect a piece of wire to the separate receiver's antenna connector and the other end placed close to the FT-101's "PB-1073" board.

Lol, I didn't even need to! That signal is LOUD and clear! I checked all the crystals, they are all what they should be. Actually I found a lot of straaaaaange signals near those ones, other radios perhaps?

Tried tuning up on 15 again, and I absolutely swept the PLATE like crazy while hunting for that tuning spot. It only produces about 3 watts and the tuning is real sharp, not easy. But it is technically producing power.

Where should I go from here?

[KC9QQM]

Glad you got on the air, I am still tweeking mine up. Plus still waiting fro a friend to give me his old tower. Only wierd thing I have found so far is that when I have selected the 40 meter band the preselector for best signal is between 80 and 160! I know it is the right band because I heard a QSO party from Texas calling CQ on 40 meter phone. Ideas why this would be that way?

73
Jeff
KC9QQM

[WA4OTD]

Great read! I have a FT101EE I bought new in 1975 (actually parents bought for me). Still works great, always has, just a couple switches that need extra care every once in awhile.

Maybe the tubes are weak on the higher bands, but I doubt it. Could be the bandswitching, if you get in and ohm out the contacts that should be making. YOu already know the basics are working since it works on lower bands.

[VA3CQC]

No, I don't think the tubes are weak in the higher bands (they were at least tested to 75% output), I think it still is in need of neutralization. Or isn't neutralized enough. But it sure produces power, about 125w peak! Sounds allright too, sometimes the bandswitch stops the receive, but a gentle nudge usually clears it up.

As for the preselector question, my preselect is fine, but my plate knob is totally outta wack. Sometimes you turn it off the end of the scale in order to tune up. So my guess is that indicator got knocked around, because the cap still makes a full 360 degree rotation. Same with the preselector, as long as the bands are in order, you'll be fine. Connect to a high-noise source like a short vertical (like a 10m vert on 160m) and make sure the edge-band edges (bottom end of 160 and top end of 29mhz) can be 'selected' using the preselector. Usually the receiver has a nice gentle peak so it's easy to find. As long as the preselector doesn't bottom out, the actual dial-face is irrelevant.

[W8JI]

No, I don't think the tubes are weak in the higher bands (they were at least tested to 75% output

Tubes do not get weak on bands. They are either weak everywhere, or they are not weak everywhere.

The reason that rumor starts is a weak tube shows up more on bands with low circuit gain or performance.

The tube itself is uniformly weak or good on all bands, but because the radio might have less gain on higher bands you might notice the weak tubes more on higher bands or on bands where alignment is off.

[VA3CQC]

I figured the tube's performance wasn't gonna change that much with frequency.

Maybe I need to open it up and play with the little neutralizing cap again? Try to get the "dip" even on both sides... Does it get 'more difficult' on higher bands? I.e. if it's not working initially on say 15m, and I neutralize it sufficiently on 30m, it'll then start close enough on 15m for me to try again? (which would in turn get it close to 12m/10m)

[VA3CQC]

I believe this radio is outputting harmonics, but somehow only in SSB and not in TUNE/CW. I want to know for sure though. Would it make sense to feed an AF single tone into the radio and listen for carriers on multiples of the RF frequency? I figure the output shall be the same in both TUNE and SSB(w/AF signal), but I will not be surprised if it is not.

Also: Is it possible that this radio was _trying_ to output harmonics all along, but they were stopped by either a filter or one of those "Ultimate Transmatch"/"Series-Parallel Capacitor" tuners that also is supposed to double as a lowpass filter? Would something like this give you (the appearance of?) normal operation?

[VA3CQC]

Oh no. I just remembered something. The tuner I got with this radio (I later sold it because I didn't like how it worked, there were like 2 inductor settings WTF? KW107 (http://www.g3ngd.talktalk.net/kw107.html)) had one of its caps all burnt from flashing-over!

Could the previous owner have just transmitted in spite of the flashovers?!?!? The burnt plate cap in the radio, the burnt tuner cap, and now my tuner's cap is flashing over too... I don't think this is a coincidence. I'm going to have to get to the bottom of this.

[KC9QQM]

Well it seems that it has been a while since VA3CQC posted so I'll jump in on my status.

I borrowed my ham clubs freq counter, RF generator, o-scope and dummy load. I was able to tune up the LO and verify the VFO is correct. Put on the dummy load and when through the transmit procedure and with my handy VX-6R as a receiver, I was able to tune and transmit on all the bands up to 30mhz. (Into a dummy load that is) but I had output to the SWR/Power meter and waveform on the scope and I head myself on the VX-6R so I am happy.

Now I just have to get my wire dipole up and tuned right for a band.

Jeff
KC9QQM

[VA3CQC]

Lucky. I don't think I had any output power still on 15-and-up last time I tried. Gotta try it again some time, I got a really sensitive power meter for it.

One thing came to mind though, I recall someone saying: "If you raise the drive and it reaches 100w, BUT you still haven't reached the end of the DRIVE control's travel, you must not go any further because an excess of drive will damage the tubes."

So, this conditions surely persists on 80m. It peaks before the knob is halfway up. But it seems there is no response UNTIL I reach this region, when I'm trying to tune up on the higher bands. Any clue what this means?

[W8JI]

Lucky. I don't think I had any output power still on 15-and-up last time I tried. Gotta try it again some time, I got a really sensitive power meter for it.

One thing came to mind though, I recall someone saying: "If you raise the drive and it reaches 100w, BUT you still haven't reached the end of the DRIVE control's travel, you must not go any further because an excess of drive will damage the tubes."

So, this conditions surely persists on 80m. It peaks before the knob is halfway up. But it seems there is no response UNTIL I reach this region, when I'm trying to tune up on the higher bands. Any clue what this means?

It could be many things, including the transmitter is oscillating and you are seeing a spurious signal. I hope the tubes you used are original specs, and I hope alignment and neutralization are right.

The FT101 is not easy to work on, because it is a relatively unstable design even when things are right. Making that worse, component access is limited. Unfortunately, they are trouble enough for an experienced tech to get right.

As radios started to become modular, they became increasingly difficult to service.

Something like an old TS520 would be a whole lot easier to work on, and is a whole lot less critical for alignment and stability.

73 Tom

[VA3CQC]

It could be many things, including the transmitter is oscillating and you are seeing a spurious signal. I hope the tubes you used are original specs, and I hope alignment and neutralization are right.
This is my first suspicion. I used GE/Motorola 6JS6C tubes, and what came out were NEC 6JC6C's. Supposedly I have heard they have differing inter-electrode capacitances that make them hard to neutralize. I've adjusted the cap on the underside until "the dip is even on both sides" or "the output power peaks as the grid current dips", as both seem to be the case. It works and it does produce 120w in tuneup and SSB on, say 80meters. The alignment is a bit off, but it can't be that bad because some people mind and some don't. It seems close enough to me at least.


The FT101 is not easy to work on... Something like an old TS520 would be a whole lot easier to work on.
Yes, but I didn't get one for free... I got this FT101E instead. It's just a coincidence I bought a FT101ZD earlier.

[W8JI]

This is my first suspicion. I used GE/Motorola 6JS6C tubes, and what came out were NEC 6JC6C's. Supposedly I have heard they have differing inter-electrode capacitances that make them hard to neutralize. I've adjusted the cap on the underside until "the dip is even on both sides" or "the output power peaks as the grid current dips", as both seem to be the case. It works and it does produce 120w in tuneup and SSB on, say 80meters. The alignment is a bit off, but it can't be that bad because some people mind and some don't. It seems close enough to me at least.



Alignment has little to do with how others hear you, at least in the context of problems I am talking about.

Adjusting the dip so each side is even is not the best way to neutralize a rig....but if you do use that method it has to be on 15 meters or some higher band. It should not be done on 80 meters no matter who says it is OK. I know this because I design PA's, and understand extremely well how they actually behave. :-)

The band where neutralization is most important is ten meters. The band where it is virtually meaningless is 160 meters. It is critical you get more than halfway to the upper frequency limit to adjust the balance in the neutralization.

The problem is this. If the rig is unstable and oscillating, neutralizing by looking at out-of-resonance plate current is often incorrect.

Regardless of what shape the rig is in, neutralizing by looking at current out of resonance is a terrible way to do it. I would disable the rig and neutralize cold.

http://www.w8ji.com/neutralizing__amplifier.htm

If you have a service manual you can go through the rig step by step. I gave away my FT101EE and FT101ZD, but at one time I had both plus extender cards to service the modules. I can't recall if it is possible to get at all the critical alignment points without extender cards, but I think not.

I wish I could help more.....but I inherited my Yaesu's from a friend who passed away and gave them to aspiring new hams after going through them. I didn't have them more than a few months before loaning them, and then eventually giving them away.

73 Tom

[VA3CQC]

So normally you would apply drive, can you not just hook up a signal generator to the input to the PA and a radio on the output? And you'd tune for minimum noise on the receiver using the neutralizing cap?