Well, I finally have all the initial parts to begin the process of the resurrection of my FT-101B. The Heathkit VTVM will be here today and I will get that inspected, cleaned up, and working....hopefully today.

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My layout of all the parts separated into bags with the card identifiers I am replacing is shown here. This resurrection process starts this weekend.?

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Cheers,?

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Butch - KA?WWT

Jacques, your guess was correct, pretty clever thinking.

Thank you for replying to message with your help.

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It was labeled NTK 112K, only have a multimeter and it measured open (no charging).

Replaced with a 100pf/3kv ceramic.

Since already in area, replaced C4 also. It was labeled NTK 302k.

It seemed to charge up with meter but very quickly.

Tried to replace with a 470pf (close to drawing) but didn't work good.

So replaced with 330pf/3kv ceramic,, it works.

It is way tight area under the PA box where switch is, very difficult to work in.?

Fortunately the new caps are much smaller than the old ones, giving some extra space.

I have acquired a complete Elko-cap replacement kit for the radio and will later start replacing all the elko's.

There are what looks like qty>50 elecrolytic caps in the kit, will be a big job. Probably work one section at a time.

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The radio is actually an ZSD model for 10W output. from Japanese market? It's same radio otherwise as the ZD

Now have the PA board for twin tubes and am considering altering for 100W.

Radio is in excellent condition.

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Thanks again!! :-))

- Full output power (sometimes) on 80m only.

- Reduced output power only at ca. 50% intermittently (sometimes) and on 80m only.

- All other bands operate normally.

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Otherwise the transceiver seems to operate normally.

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Invite ideas on what to look for.

Thanks for your suggestions Bruce.

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I have both a DVM and an old analog Simpson 260 VM. I love analog meters. An O’scope is the one thing I don’t have but I do have access to one. I have use O’scopes in my previous life as a Ground Radio Repairman in the Air Force and as a Satellite Controller/Maintainer supporting the AF as a contractor. I have been around amplifiers and radios of some type for a long time…..and I am a recently retired network engineer geek too.?

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Butch - KA?WWT

And most inexpensive digital O’Scopes have a built in signal generator!!

#2 an inexpensive digital oscilloscope and learn how to use it.?
#1 a decent digital volt ohm meter.?

It is amazing what you can do with those two pieces of test equipment.?

This is what I found in a Japanese 101ZD manual:

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I uploaded a much better version in the files section!!

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Erwin, PA3DAF

Thanks Tom,

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I have all of your recommended items. Appreciate the encouragement. ?How did you use your VNA?? I have one, never even figured about using it.

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I’m glad I asked a you answered.

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regards, ?

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Butch - KA?WWT

I just went through the same exercise and recommend: good internet connection to reach this group, good soldering station , solder wick,? non-conductive alignment tool set, bright light (with magnifier if possible) and a VNA. I have some other stuff, but this is what got me through rebuilding rectifier board, replacing caps, and realignment.? Good luck! Big fun. I had 75 email exchanges to get through it, but I'm an idiot. You'll do better!

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73,

Tom ai4th

To the greater group,

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As I begin the project of bringing my FT-101B back to life, I would like to know what one piece of test equipment, other than a multimeter, would you suggest I have in my arsenal to assist in my troubleshooting efforts and to help me bring this radio back to working condition.?

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I recently did a rather thorough inspection of all the replaceable cards as well as the chassis wiring and electronic components. I have discovered about 14 mylar and mica capacitors that will need to be replaced due to cracking. I have received the electrolytic capacitor replacement kit and will start down this road once the other additional caps come in.

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Is there a single 'gotta have it' piece of gear I should be looking for? ?I have my eye on a couple of different VTVM's but maybe I should be looking in a different direction.?

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Thoughts and replies are most appreciated and welcomed too.?

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Butch - KA?WWT

Hello Joseph,

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I have replaced the PB-1077B on my FT-277 with the later PB-1181. You may need to perform a realignment of the radio afterwards.

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I have placed a file into the Files section, of the PB-1077B info that might help.

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73,

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Peter

G4DJB

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In my case I just got one a few weeks ago.

It has physical taps for 110 & 117 but, when measured/rung out, it seems they are not connected internally.

Thus, I'm using an auto transformer to get the 100 volts.

The real fear with the S model is that the power transformer’s primary is only wound for 100vac. There are a number of people stating that there are no other primary taps on the S version.?

That would make it actually a different PT with a different part number…. Etc.?

Yes, the ZD & ZSD are basically the same radio except the PA section is a single bottle in the ZD. So the PA section is different. I have the ZD Service Manual but don't know if they even printed a manual for the ZSD.

Hi Everyone,

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I am currently restoring a 1st generation ft-101 (actually a ft-277...) and while smoke-testing it I found that the RF board may need to be repaired or replaced; Therefore, I have two questions:?
- Does anybody have a drawing of the PB-1077B board with the parts indicated? (the yaesu manual shows just a few of them)
- Apparently the PB-1183 board can also work in an old ft-101, and it can still be found; has anybody tried the replacement?

Any help or advice will be appreciated!
Best Regards, and Season's greetings to all
73 - Joseph F4JVO?

is the service manual for the ft-101zd if that matches the zsd I don't know.

maybe someone else can advise the differences and if the info/schematics would be a match.

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73

VAEDPZ

John V. Now a proud owner of an FT-101 ?

Thanks Bruce.

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The cap replacements should be here by the weekend. I’ll start with the replaceable cards first then tackle the two large caps after I take some more up close and personal pictures of the bottom side of those caps.?

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I’m also reading, and rereading the service manual and am attempting to do a signal path trace rx/tx on a copy of the schematic. I did this a lot during my training days in the AF and it helped me quite a bit.?

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The service manual is written well from what I have read so far….which makes it nice.?

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I’ll keep you posted as I go along here.

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Regards.

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Butch - KA?WWT

OK. Lots of stuff to look over.
most of these in good condition look like new from the bottom!

Old Electrolytic capacitors can be troublesome though.
Sometimes the bias supply filter caps can be going bad. That will cause the negative supply voltage to drift closer to zero and create an under biased condition. If so, you’ll never be able to dial in enough negative voltage to bring the idle current down.?
Re-capping the regulator power supply board is pretty easy to do. Just remember that the bias supply is all negative voltage and the positive legs of the capacitors are at ground potential.?

Bruce,?

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Thank you for your reply. My answers below:

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USB/LSB/Tune: all three positions, no microphone, PTT to MOX only. Bias pot to minimum and that is the lowest reading I can get to.

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I have been bitten too many time in the past to know that power rules and a am just a pawn to it. ; - ) (Ground radio repairman in the Air Force and satellite controller and network engineer/SME as a contractor.). I have been around RF for a long time. Nothing raises the hair on the back of your neck more when you are standing next to a 10KW TWT (glycol cooled) and 30,000VDC right behind a piece of glass. I shudder to this day. ;-)?

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I don't have a tube checker, visual inspection (original tubes) show no bad indication (does not tell the whole story though). The getter on all three tubes look great.?

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Yesterday I took out almost all the removable cards on the top side, inspected them, took many, many pictures of all components. and replaced them. (I'll remove the frame and get to the ones I had no room to remove.?

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Today I opened the bottom, initial picture of what I saw upon removal of bottom cover. The freaking thing looks like it just came off the shelf. All the inspection paint marks are still in their factory spots. It looks like I opened a time capsule of an extremely well preserved FT-101B.. So now I am even more wary of it. I don't want to screw anything up!!! ?

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Slow, maybe even too slow will be my mantra here. I ordered the cap replacement kits and after I feel good about that will start down that road. But, I don't even want to do that before I have had a chance to inspect it more and talk with as many experts here and anywhere else I can first.?

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I shall take your suggestions to heart and do just that.?

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Please don't take this the wrong way. Joining Facebook is and always will be a step too far for me.?

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Regards,?

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Butch - KA?WWT?

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Butch - KA?WWT