FT101ZD Mk1 AM RX but no SSB/CW
Hello fellow boat anchor enthusiasts. I have here a very clean FT101ZD Mk 1 recently donated by a colleague. It arrived with him with a known no TX fault. I have not done any TX tests yet. Just trying to get it to receive at the moment. The set only receives on AM - not on SSB / CW. There has been some work done on this set over the years so some red herrings may be in there somewhere. This set used to have RX on all bands but very unstable, (fast frequency jitter). I have been told that after pulling and replacing the three plug in boards, (RF unit, Pre-mix unit, Pre-mix local unit), the set went deaf to all but AM, . All co-ax connections checked OK and in the correct positions. Card slot pins all look fine. No busted tracks on pcb's.
Clues:
Clearly audible hiss in speaker on all non-working modes. AF PA good.
Very quiet SSB heard among the hiss with NB on and AF volume all the way up. Very unstable by the sound of it. Almost inaudible but it is there. Could just be induced across loom somewhere.
Dim control at full bright drops hiss volume a little bit. (12V rail).
All power rails check OK on Rect. A and Rect. B boards. 8V present on all mode settings at J1, AF pcb, pins 1,2,3 and 4.
3rd digit from left on display non functional, (Possibly Q10 or Q4 on display pcb - will tackle this later. Swapped segments and fault stays at position 3). Herring. It did this before going deaf.
When turning the RF gain with ALC off the AM RX is only present in one position. Increasing RF gain knocks out the signal again. There is only one "sweet spot" as it were.
AM signal sounds very over modulated. Better with ALC on.
Relays click in and out briefly sometimes when switching out of AM mode. (VOX? "clunk" through PA?). Possible herring.
Checked Q13, Q14, (FET), and Ge diodes D2 to D5 on AF pcb - all OK.
Continuity through relay on AF pcb OK.
There is a very slight hum in the speaker with volume down. This has occurred since set went deaf. 8V regulator on lower chassis side rail gets a little warm but nothing alarming. Steady 8V out for 12V input.
Clarifier seems to only shift one way on RX.
ATT switch scratchy but common to all modes, (I think), so doesn't explain lack of SSB / CW.
The pre-select control seems to need very little adjustment over each band to pull in AM stations compared to my Mk3. Fishy but also possibly non-herring.
Rotary band and mode switches cleaned and seem to be working fine. No crunching / crackling when wiggled.
Looks like more than one fault here. If I can get the SSB / CW RX back I can then tackle the frequency instability issue. Maybe it will even transmit one day!
Many hours spent with service manual and trying to understand all the frequency conversion stages in this set. Took me years to figure out what an IF actually is!
Very aware of 900V / 300V and how to discharge it before working on set. I'm 56 and still here!
Any input / advice most appreciated. I have a working Mk3 but loathed to start board swapping just for the sake of it. These sets are a real gem so it would be great to revive another one.
Thanks in advance. Have a good day everyone.
David, M0LFD
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Re: New FT-101ZD owner w/ issues: NO TX/RX, digital display won't change freq ..
Page 6 of User Manual and page 1-8 of Service Manual both show ACC plug with link
Note:? It is very easy to touch the feed through caps with 300v on them with a finger at same time touching the chassis !
George, G8AOJ
Alrighty Update-? ?I found the ACC plug. Was staring right at me.? ?Will report back on the progress , thanks again!?
-- George Smith? - RSGB, Dean Forest Railway, H&GCT & Cotswold Canals Trust member
?
Tel:? 01594 835 736 (home)
?
?
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Re: New FT-101ZD owner w/ issues: NO TX/RX, digital display won't change freq ..
Alrighty Update-? ?I found the ACC plug. Was staring right at me.? ?Will report back on the progress , thanks again!?
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Re: New FT-101ZD owner w/ issues: NO TX/RX, digital display won't change freq ..
Hi Greg,?
Appreciate your input.? Do you know of a commercially available 11 pin plug/link by any chance?? I am looking through the owner's manual online for the 'ZD' and cannot find a mention of a link or plug that enables the RX/TX or use of the digital display.? The text description of the display only talks about the wiring within the chassis but no plug/link.? Perhaps I am not seeing it.? Will investigate further into this.??
10-4 on the HV present within the chassis, I'll treat this just I do amplifiers with the upmost caution to ensure the HV is dissipated and the "one hand in pocket" technique my grandfather shared with me back in the day.?
My understanding is the tubes DO power on though.? Which is odd if a link/plug was needed.? Would you mind pointing me in the right direction within the manual or the schematic?? Thank you, sir!?
~Bryan?
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Re: New FT-101ZD owner w/ issues: NO TX/RX, digital display won't change freq ..
Needs a link in ACC socket on rear panel to transmit.
You will need an 11 pin plug. Link pins? 1-2 to get the heaters to power.? Tube will no light otherwise.
If the RX gives sound output and the tuning knob (VFO) will find stations - investigate the display unit.?
If noise out but no stations check the RF input fuse (bulb) then the oscillators. If nothing out? not even noise check the audio stages first.
BEWARE:? The HT (900 volts dc) is always ON even if the heater switch is OFF and in the transceiver is in receive mode.? 900v and 300v present on the underside of the chassis and in the PA compartment.? Beware of the 300v on the feed through capacitors on the driver compartment.? It bites !? 900v present on the RECT B board and transformer tags.
Good Luck
George,? G8AOJ (UK)
Hello everyone from Colorado!?
For years been wanting to get a FT 101.? My grandfather had several 101's since the 50's but when he exited the hobby 15 years ago, sold them all.? To me the 101 is a handsome rig and remembering my grandfather operate his brings back great memories.?
I found a FT-101ZD in FL several days with some issues.? Its SN is: 9F-060716 which makes it an April 79' rig and a MK0 "ZD".? The radio powers on and "tubes light" but with no TX or RX.? The display stays stuck at 0.200.0 and won't change frequencies either. I am still waiting to receive the radio but I would like to get a "head start" ..? Although considered a "hybrid" radio, it still is HUGELY mechanical. My first thoughts are perhaps the rod/linkages might be busted.. * maybe *.
I have ordered the service manual and owner's manual as well and waiting on those as well. Might you fine folks here chime care to share your thoughts, experiences etc.? I would certainly appreciate it.??
73?
Bryan, KB9UZO?
? 
-- George Smith? - RSGB, Dean Forest Railway, H&GCT & Cotswold Canals Trust member
?
Tel:? 01594 835 736 (home)
?
?
|
New FT-101ZD owner w/ issues: NO TX/RX, digital display won't change freq ..
Hello everyone from Colorado!?
For years been wanting to get a FT 101.? My grandfather had several 101's since the 50's but when he exited the hobby 15 years ago, sold them all.? To me the 101 is a handsome rig and remembering my grandfather operate his brings back great memories.?
I found a FT-101ZD in FL several days with some issues.? Its SN is: 9F-060716 which makes it an April 79' rig and a MK0 "ZD".? The radio powers on and "tubes light" but with no TX or RX.? The display stays stuck at 0.200.0 and won't change frequencies either. I am still waiting to receive the radio but I would like to get a "head start" ..? Although considered a "hybrid" radio, it still is HUGELY mechanical. My first thoughts are perhaps the rod/linkages might be busted.. * maybe *.
I have ordered the service manual and owner's manual as well and waiting on those as well. Might you fine folks here chime care to share your thoughts, experiences etc.? I would certainly appreciate it.??
73?
Bryan, KB9UZO?
?
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Re: FT-101B Parts 2,3,4 schematics
Nothing yet.? My qrz.com email address is:
kn7sfz@...
Same one I use to receive on this list...perhaps try again?
Richard
On 2/27/2023 11:56 AM, Todd AL7PX via
groups.io wrote:
toggle quoted message
Show quoted text
Hi Richard:
Sent you a email to your QRZ address.
Todd
AL7PX
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Re: FT-101B Parts 2,3,4 schematics
Hi Richard:
Sent you a email to your QRZ address.
Todd
AL7PX
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Re: FT-101B Parts 2,3,4 schematics
Well, I see it was reduced to an unusable size,
so shoot me an email Todd and I get it to you.
Lots more files here on Facebook:
kn7sfz
On 2/27/2023 11:44 AM, Richard kn7sfz
via groups.io wrote:
toggle quoted message
Show quoted text
Hi Todd,
Here is a full schematic from the Facebook FT-101 group.? It's 6
megs, so hope it makes it or if not, email me direct at:
kn7sfz@...
Richard kn7sfz
On 2/27/2023 11:32 AM, Todd AL7PX via
groups.io wrote:
I can't find part 2 or more parts to the full schematic for the
101B files. Part 1 full schematic is listed but no further. Is
it located somewhere else?
The copies are the best I've seen and would like the full
schematic set. Does anyone have the other parts?
Todd
AL7PX
|
Re: FT-101B Parts 2,3,4 schematics
Hi Todd,
Here is a full schematic from the Facebook FT-101 group.? It's 6
megs, so hope it makes it or if not, email me direct at:
kn7sfz@...
Richard kn7sfz
On 2/27/2023 11:32 AM, Todd AL7PX via
groups.io wrote:
toggle quoted message
Show quoted text
I can't find part 2 or more parts to the full schematic for the
101B files. Part 1 full schematic is listed but no further. Is it
located somewhere else?
The copies are the best I've seen and would like the full
schematic set. Does anyone have the other parts?
Todd
AL7PX
|
FT-101B Parts 2,3,4 schematics
I can't find part 2 or more parts to the full schematic for the 101B files. Part 1 full schematic is listed but no further. Is it located somewhere else?
The copies are the best I've seen and would like the full schematic set. Does anyone have the other parts?
Todd
AL7PX
|
Hello Bruce:
D13 was bad. I also put a better trimmer for the adjustment.?
Todd
AL7PX
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Which diode was bad Todd??
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42 years for a dry joint from manufacturing to cause a problem!
Well, we all know that dry joints are caused by the joint not being heated enough when the joint is being formed. However, this one took 42 years to cause trouble! From the serial number, my FT-101ZD was manufactured in 1981. Last week, I noticed that it was low on receive on 10m, but seemed perfectly fine on the lower bands. I came here and had a read about causes for the rig being deaf. Checked the ATT switch and cleaned it with switch cleaner, checked the continuity of the fuse bulb and checked that I was getting S9+10db on 14.2MHz from the calibration oscillator. All checked out fine. I didn't think that it would be any of them anyway as the rig seemed to work perfectly OK on other bands. I was then looking for something specifically related to 10m, but in the end, that wasn't the case. I connected the antenna to the RX output and the sensitivity was fine, so I started looking for issues with the components near to SO239. Sure enough a dry joint was found where the inductor from the SO239 connected to the tx/rx relay nearby. A quick resoldering of this joint and my 42 year old rig was back to her former self in terms of sensitivity. I spent most of my working life in electronics, so I have seen plenty of crystaline "dry" joints in my time, but I've never known one to take such a long time before it actually caused an issue. When I looked under the sleeve (circled in the photo), the end of the inductor went through the relay terminal and was dangling loose in mid air with an obvious dry joint on the end of it. Why it only caused issues on 10m is a bit of a mystery, 12m was OK, 15m was fine too, although I guess that on lower bands the actual receive voltage from the antenna will be greater, so that may well be why. Seems a bit odd though. Anyone can beat this record time for a dry joint to cause issues? ;-) 73 de Gordon G8WWD 
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I've been been adjusting and checking my old 101B and find I do not have correct voltage on clarifier terminal on VFO during receive. I'm only getting .850 volts, less than a 1 volt.
If I zero the clarifier and transmit I can match voltage with the zero adjustment pot. Roughly 3.70 voltage. I have a good supply voltage of 6 0 volts, and steady. Anyone see these conditions before, any help would be appreciated.
Todd
AL7PX?
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Re: Hard of hearing FT-101EX success!
Hello Richard - Just working backwords thru messages.? After much reading and thinking I think that the first RF Amp transistor is probably the culprit - although some have said another one can give trouble.? I have two concerns which are sort of associated: the only 3SK51 devices I have seen for sale over here are very expensive (and some advertised are not in fact that device.? Secondly my 101Z is in complete original condition (I bought it new 42 years ago) and I am reluctant to go unsoldering stuff unless I know it is the right device!? I have seen something that said a 40673 would replace the 3SK51 - and I have some of these from my 'construction period some 40 years ago!? No test gear so cannot go down that route.? Appreciate your interest and help. Alistair GM4ENF.
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Re: Hard of hearing FT-101EX success!
Hello Richard - just catching up after a few days away from home.? email is alistairfyffe@...Alistair GM4ENF
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Re: Hard of hearing FT-101EX success!
Thanks Kenoli,
Richard
On 2/15/2023 9:55 AM, Kenoli Oleari
KB6EMG wrote:
toggle quoted message
Show quoted text
A simple way to send big files for free is wetransfer.com. ? ?It
is free up to 2 GB and very easy to use. ?Just drag the image onto
the page put in the send and receive email address and push a
button. ?For security they often send a security code to your
email address.
It sends the addressee an email when it is ready to download.
—碍别苍辞濒颈
On Feb 14, 2023, at 8:25 PM, Richard kn7sfz
<kn7sfz@...> wrote:
Alistair, I see the schematic
attachment didn't make it intact, so if you'd like
to send me an email direct, I'll get it to you.? It
is 6 megs, so hope your email provider can handle
that.
Richard?
kn7sfz@...
On 2/13/2023 5:00 PM,
Richard kn7sfz via groups.io wrote:
Hi Alistair,
I tried to find a quality manual for your 101Z
online but they are all low resolution, however it
is obvious that your RF board is different from
the one in the FT-101EX. The good news is that
their RF MOSFET amplifiers are basically the same,
yours being the 3SK51 and mine the 3SK40, either
of which can be replaced by the $6 NET 454 off
Amazon, which I used to bring mine back to life.
I have attached a high res copy of the 101E
schematic and you can see the 3SK40 transistor in
the outlined PB-1181 RF board.? Sorry, I have no
way of highlighting it.? It is socketed, so that
made replacement quite easy.? I'm sure the
transistor is socketed in your board as well.?
Great care must be taken that you get each of the
four leads in their proper place when installing
the new transistor...very difficult for these old
eyes, even using a magnifying visor.
Good luck on your project and hope to hear of your
success,
Richard kn7sfz
On 2/13/2023 8:16 AM,
Alistair GM4ENF via groups.io wrote:
Hello Richard - good you got to the bottom of
problem.? I am interested in the subject; can you
post a copy of the circuit diagram highlighting
the semiconductor you replaced?? May help me to
cure my own hard of hearing 101Z
Alistair (Al) GM4ENF
|
Re: Hard of hearing FT-101EX success!
A simple way to send big files for free is wetransfer.com. ? ?It is free up to 2 GB and very easy to use. ?Just drag the image onto the page put in the send and receive email address and push a button. ?For security they often send a security code to your email address.
It sends the addressee an email when it is ready to download.
toggle quoted message
Show quoted text
On Feb 14, 2023, at 8:25 PM, Richard kn7sfz <kn7sfz@...> wrote:
Alistair, I see the schematic attachment didn't
make it intact, so if you'd like to send me an email direct, I'll
get it to you.? It is 6 megs, so hope your email provider can
handle that.
Richard?
kn7sfz@...
On 2/13/2023 5:00 PM, Richard kn7sfz
via groups.io wrote:
Hi Alistair,
I tried to find a quality manual for your 101Z online but they
are all low resolution, however it is obvious that your RF board
is different from the one in the FT-101EX. The good news is that
their RF MOSFET amplifiers are basically the same, yours being
the 3SK51 and mine the 3SK40, either of which can be replaced by
the $6 NET 454 off Amazon, which I used to bring mine back to
life.
I have attached a high res copy of the 101E schematic and you
can see the 3SK40 transistor in the outlined PB-1181 RF board.?
Sorry, I have no way of highlighting it.? It is socketed, so
that made replacement quite easy.? I'm sure the transistor is
socketed in your board as well.? Great care must be taken that
you get each of the four leads in their proper place when
installing the new transistor...very difficult for these old
eyes, even using a magnifying visor.
Good luck on your project and hope to hear of your success,
Richard kn7sfz
On 2/13/2023 8:16 AM, Alistair GM4ENF
via groups.io wrote:
Hello Richard - good you got to the bottom of problem.? I am
interested in the subject; can you post a copy of the circuit
diagram highlighting the semiconductor you replaced?? May help
me to cure my own hard of hearing 101Z
Alistair (Al) GM4ENF
|
G8AOJ
wheelz
Bruce Collins
Alistair GM4ENF