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Restoration of an Yaesu FT-101E.  

Below is the electrolytic order sheet.     The quantities are doubled so I can build my inventory. 


Verify quantities against your parts list.  I ordered double quantities.


You will see the note "FT101E for 16v SUB".  This is where a cap was not available in the lower voltage.  Or I just wanted to minimize bins.  


All these caps are selected with 105 deg Celsius.  The original caps are 95 deg C.  


All caps are Radial.  The leads were long enough to stretch for axial replacements.  Use a bit of Heat Shrink Tubing or spaghetti.


Add C13 80pf 1kv and C131 1000pf 1kv (the factory installed  capacitor is 500volts) to your order.  One is a coupling cap from the driver tube to the PA tubes and the other looks to be feedback. Degradation causes high tube bias and excessive heat.  This was advised by a FoxTango contributor.  These are below the electrolytic cap list.


Add R37 18k 5w and  R5 5.1k 5w resistors.  I found R37 cooked.  It had been arcing to the chassis from an exposed section of the resistor body (missing insulation). The cap above it was cooked too.  It is a suggested mod of a 50 uf at 450 v.  I did not replace it. These resistors cook it. 


Go see FT-101 HF Transceiver Web Page ... for  FT-101 information.


The biggest challenge is to find complete alignment information.  Some information is found on the board detail pages for each board.  And most of the alignment adjustments are inferred.  One must use experience and good judgment to determine the best setting of individual pots, trimmer caps and tuning slugs.  I have documented all of my setting with in my copy of the service manual.


IMG_1668.JPG (123415 bytes)It is best to use an external power meter when tuning up the 101.   IMG_1669.JPG (100105 bytes)Keep an eye on the plate current.   IMG_1741.JPG (231186 bytes)What is this trimmer cap for?    
IMG_1532.JPG (85803 bytes)Cleaning the cabinet with Brasso. IMG_1533.JPG (56473 bytes) IMG_1534.JPG (63402 bytes)The grit in Brasso helps remove dirt and corrosion.  IMG_1535.JPG (82882 bytes) IMG_1536.JPG (82159 bytes)
IMG_1537.JPG (81463 bytes)        


And now for some of the challenges that I encountered.


Finding a matching schematic.  

I had found discrepancies with the schematic that I was using for the 101E and this unit.  There is a coil and two capacitors in the shape of a tank circuit from the lamp to the relay.  Then a wire from the relay to the Receiver RCA jack.  The schematic shows no such components.  

Peter of Surry UK G4DJB offers: 

"Schematics - do not believe them 100%. I have also found differences between my 101E and the schematics, plus you will find that there are a number of different versions of schematic just for the 101E alone. Unfortunately, Yaesu did not mark them any differently (they could have put a version number or date on them) so there's no way of telling which schematic you have. It sounds as if you have a late model 101E and the schematic for an earlier 101E. I'll see if I can find a copy of the late 101E schematic for you. I do have one that shows the components between the lamp and relay as you describe, but its part of a very large pdf file - far too large to email or upload to the files section."

And he did send me a schematic that matched the unit.  Thanks again Peter!

This Late Model schematic can be found at: http://groups.yahoo.com/group/FoxTango/files/FT-101E_Late_Sch.pdf


Heterodyne Output adjustment (p 7-8)

Note - With a rig of this vintage I would perform the Power supply voltage adjustments p 7-11 then Heterodyne Alignment as my first two alignment steps.  I went through the whole preselector balancing procedure only to find the Heterodyne oscillator signals were in need of alignment.  This may or may not affect the rest of the alignment.  But is dose seem to be a logical thing to do.  

I was trying to set the initial oscillator amplitude of 0.3 v rms with the trim pot and the T111 but could not get the amplitude.  I used a scope looking for 0.8484 volts p-p.   Page 7-8 of the service manual.

Also the trim pots do not line up with the FT-101E band dial.  This unit 10D band is adjusted with TC-23 and not TC-24

The second paragraph on page 7-8 does not address all of the crystal trim pots (6 out of 11 trimmers).  Is there a reason for this omission? I set them all for .3 rms (.8484p-p).

R22 on PB-1181 should be 56 ohms oscillator buffer transistor emitter resistor.  It was 22 ohms.  This held the TP signal below the .3 v rms.  Once I changed this to the schematic value I could properly set the oscillator levels.  It looked to be factor, w/ properly bent lead so it would push too far through the PC hole and beige color coated (not the value bands).  Boy I fought this for hours changing both oscillator transistors before I started measuring discrete resistors and found it (first resistor I measured by the way).

I had removed a couple of resistors that were oldered across the trim caps used for the level control.  Once R22 was the correct value these bands could not be set low enough and had distorted sine waves.  So I put those
undocumented mods back.  160 meters took an 820 ohm parallel resistor to the trim cap, 40m took a 1000. 

This rig was set up for C.B.  I have been removing the changes and restoring this unit to original configuration.

I was informed by Peter of Surry G4DJB, UK a FoxTango Yahoo group participant, "R22 on the PB-1181 was changed in value (by Yaesu) in the last production batch of FT-101E radios from 56-ohms to 22-ohms. It seems as if your radio prefers the old values!"

With a rig if this vintage and age I would perform the Power supply voltage adjustments p 7-11 then Heterodyne Alignment.  I went through the whole preselector balancing procedure only to find the Heterodyne oscillator signals are whacked out.  

I used a O-scope to set the levels and some of the crystals did not present a sinusoidal wave shape.  "This is normal."  Peter of Canada VK4JD said, "I noticed this when tuning up a 101Z recently.  The TX output was clean on the spectrum analyzer and I didn't detect and RX spurious related to oscillator multiples."  A spectrum analyser is good enough for me.  I also check for the harmonics on a communications receiver. 

NTE-454 Front End FET upgrade (Q1 PB-1181 3SK40M)

I tried the NTE 454 FET recommended on the FoxTango site. I heard very little improvement over the stock FET.  I ordered two.  The first NTE454 degraded the reception.  It curiously came re-heat sealed from Mouser.  The second was in original blister packaging.  Both had anti-static warnings. The second NTE454 had a barely perceptible improvement with .3 uv input or there about.  I suspect people that have heard a noticeable improvement may
have had compromised (damaged) original FETs.

Now please realize, if you need a new Q1 FET this would be a fine substitute. 

VR-1 on PB-1181, there is a note tucked away in the corner on Page 5-11 of the Service Manual that says that "VR-1 is set for minimum signal level at 3840 kHz when transmitting on 3800 kHz as heard in a separate receiver".  From Peter G4DJB.


S-meter adjustment  and. NB Adjustment.

Page 7-9  (VR-2 PB 1183, Q5 emitter) I was not able to get the S-meter to 20 over 9 with 50 uv at 14,200.  When I wiggle the lamp in the socket the signal jumps a bit. When I short the lamp socket with a screw drive the signal pick up 2 S units.  But it never reaches the 20 over 9 reading.

The solution is two fold.  Clean the fuse/lamp socket and lamp base and re-solder the lamp socket leads.  This stabilized the receive signal when the lamp was tapped.

The low S-meter reading generated discussion on the FoxTango Yahoo group, relative to the accuracy of S-meters in general (and some specific).  The bottom line for me is the calibration did not meet the criteria set by Yaesu.  And that is an indication of trouble.

The solution is to align the IF sections of the circuits before this board  See Noise Blanker below.



Noise Blanker PB-1583 (the FT-101e version)

The break through that restored the S-meter sensitivity and the whole receiver's sensitivity, came when adjusting TC1 and T120 on PB-1583 p 5-35.

Starting at the IF input (3180k) with the internal marker Generator on, set to produce a 100hz tone, use the S-meter for peak indication.  "Rocked" the transformer T120 while peaking TC1 (just like the 600khz alignment on an AA5) and WOW!.  The S-meter reading kept climbing and climbing.  Off the scale....pegged!  Reduced the RF gain to keep the meter on the scale and kept rocking and peaking.

What a difference!  I put a random long wire on it (the one thrown up into the trees) and started pulling in stations from all over on 20m!  I am tickled pink.  I now could then back down the S-meter setting (VR-2 PB 1183) and set it to 20 over 9 with 50uv at 14.200 as in the cal procedure. 

I continued on with the 455k transformer, T123.  A receive signal is needed for proper adjustment of T123.  Again set the internal marker generator to output a 1000 Hz tone, NB switched on, O-scope on the TP and dip the DC for minimum.  You need to receive a signal to generate AVG. 

I tested the NB by taking a Weller soldering gun, wrapping the long wire antenna around it and alternating the trigger switch from high to low power.  The NB works as indicated by the S-meter staying steady with the NB on.


Cold Neutralization of the FT-101, 

by Peter Roberts G4DJB

Also found on the Fox Tango International Forum Index

The standard neutralization method used by FT-101 owners suffers from a couple of major drawbacks - the finals are producing RF (i.e. are `hot') and the method requires a lot of tweak and try. This results in a lengthy process during which the finals may get very hot, or may even be destroyed if they should go into oscillation and the operator is not quick on the OFF switch. The method described here is not new, but may be new to some FT-101 owners. It allows neutralization of the finals whilst they are `cold' (not actively producing RF). The operator may therefore take their time and there is no chance of the finals being damaged.

As pointed out, this method is not new. Please refer to an excellent website by Tom, W8JI (www.w8ji.com/neutralizing__amplifier.htm) in which he discusses the need for neutralization and ways it may be achieved. The cold neutralization method works as it takes advantage of the fact that inter-electrode capacitances are present whether the device is `hot' or `cold'.

In a `cold' device, the grid-plate capacitance acts as a path through the circuit, and so a proportion of the drive signal will appear at the output. The purpose of neutralization is to couple an amount of signal back to the driver equal in amplitude and in antiphase to the finals' grid-plate coupled signal. So, the net effect should be to cancel out any signal feed through. In practice, cancellation will not be complete, but it is possible to adjust for minimum feed through.

In the FT-101, `cold neutralization' is achieved as follows:

1. Make sure that the transceiver has the PA compartment covers fitted (top and bottom).

2. Switch on the radio. Tune the radio as normal for maximum transmitter output (into a 50-ohm dummy load) at 29.0 MHz. Switch off the radio. (You can miss this whole step if you are worried about the finals oscillating)

3. Remove the "Accessory" plug from the rear panel. This opens the heaters in the finals, but keeps the heater active in the driver.

4. Connect the transceiver RF output (ANT connector) to a detector of some sort. (I use an oscilloscope with a BNC "T" piece adaptor, the third arm of which has a 50-ohm termination directly mounted to it. A standard communications receiver will probably be too sensitive, may suffer damage, and may not give accurate results).

5. Switch on the transceiver, and switch on the Heaters. Make sure that the finals are not lit, but that the driver is!

6. Set frequency to 29.0 MHz and set the mode switch to TUNE.

7. Set the carrier level control to about 3 and set the MOX/PTT/VOX switch to MOX.

8. Adjust the Preselector, Plate and Load controls for MAXIMUM signal on the detector (scope). Adjust the carrier level as needed to get a suitable level.

9. Adjust the neutralization capacitor TC27 (using a non-metallic trimming tool) for MINIMUM signal on the detector.

10. Re-peak the Plate and Load controls for MAXIMUM and re-adjust TC27 for MINIMUM. Repeat until no further reduction in signal at the detector can be achieved.

11. Set the MOX/PTT/VOX switch to PTT, the heater switch to off and the radio power switch to off. Remove the detector from the ANT connector and re-fit the Accessory plug.

You should now find that maximum RF output coincides with the dip in Ic, or is very close to it.

Detector Notes.
The choice of `detector' is entirely up to you. There may be up to 1-Watt RF present during this process, so you will need to act accordingly. As stated above, a communications received is probably not a good idea. I found that a lot of attenuation was required between the FT-101 ANT connector and the radios' antenna terminal and that RF was leaking around the attenuators making accurate adjustment impossible. As an alternative to an oscilloscope, a simple detector (perhaps following a 50-ohm attenuator) using a diode and multimeter should be adequate. For making adjustments, an analogue meter is preferable to a digital one.



I have some more procedures developed.  I will be adding these at a later date.



In conclusion

Peter of Surry UK G4DJB puts it,

I must extend thanks to all the contributor on the FoxTango Yahoo group.  As the Beatles sang, "With a little help from my friends."



PARTS as of 2009

This is the list of parts that I replaced  for this restoration.  You should be able to click on the Mouser # then add a quantity to your cart.  I hope this saves you some time.

                        Part Numbers                                                                           Customer Label         Suggested QTY        

Mouser #:
5985-85-500V100K FT101E 4
Mfr. #: 380LX101M500K022
Desc.: Snap-In Electrolytic Capacitors 500V 100uF 30X30
Mouser #:
Mfr. #: UVZ2W2R2MPD
Desc.: Radial Aluminum Electrolytic Capacitors - 105 Degree 2.2uF 450V 105c 10x12.5 '20% 5LS
Mouser #:
647-UVZ1E471MPD1TD FT101E 4
Mfr. #: UVZ1E471MPD1TD
Desc.: Radial Aluminum Electrolytic Capacitors - 105 Degree 470uF 25V 20%
Mouser #:
647-UVZ1C221MED FT101E 10
Mfr. #: UVZ1C221MED
Desc.: Radial Aluminum Electrolytic Capacitors - 105 Degree 220uF 16V 105c 6.3x11 20% 2.5LS
Mouser #:
647-UVZ1H330MDD FT101E FOR 16VOLTS 5
Mfr. #: UVZ1H330MDD
Desc.: Radial Aluminum Electrolytic Capacitors - 105 Degree 33uF 50V 105c 5x11 20% 2LS
Mouser #:
647-UVZ1H220MDD FT101E FOR 16VOLTS 4
Mfr. #: UVZ1H220MDD
Desc.: Radial Aluminum Electrolytic Capacitors - 105 Degree 22uF 50V 105c 5x11 20% 2LS
Mouser #:
Mfr. #: UVZ1H2R2MDD
Desc.: Radial Aluminum Electrolytic Capacitors - 105 Degree 2.2uF 50V 105c 5x11 20% 2LS
Mouser #:
647-UVZ1H100MDD FT101E SUB FOR 16VOLT 20
Mfr. #: UVZ1H100MDD
Desc.: Radial Aluminum Electrolytic Capacitors - 105 Degree 10uF 50V 105c 5x11 20% 2LS
Mouser #:
Mfr. #: UVZ1H470MED
Desc.: Radial Aluminum Electrolytic Capacitors - 105 Degree 47uF 50V 105c 6.3x11 20% 2.5LS
Mouser #:
647-UVZ1H010MDD FT101E sub for  16V 22
Mfr. #: UVZ1H010MDD
Desc.: Radial Aluminum Electrolytic Capacitors - 105 Degree 1uF 50V 105c 5x11 20% 2LS
Mouser #:
647-UVZ2E220MHD FT101E 6
Mfr. #: UVZ2E220MHD
Desc.: Radial Aluminum Electrolytic Capacitors - 105 Degree 22uF 250V 105c 12.5x20 20% 5LS
Mouser #:
647-UVZ2C220MPD FT101E 4
Mfr. #: UVZ2C220MPD
Desc.: Radial Aluminum Electrolytic Capacitors - 105 Degree 22uF 160V 105c 10x16 20% 5LS
Mouser #:
647-UVZ1E102MPD FT101E 4
Mfr. #: UVZ1E102MPD
Desc.: Radial Aluminum Electrolytic Capacitors - 105 Degree 1000uF 25V 105c 10x20 20% 5LS
Mouser #:
647-UPW1C101MED FT101E 18
Mfr. #: UPW1C101MED
Desc.: Radial Aluminum Electrolytic Capacitors - 105 Degree 100UF 16V

as of May 2009



This is a second order for C13 the coupling capacitor from the 12BX7 to the final output tubes.  Q1 is a FET that exceeds the performance and has diode input surge protection.  It is alleged to significantly improve the sensitivity of the 101 (I believe it but have not tried it yet). 


Mouser part number and description.


 Qty per chassis

C13 coupling capacitor, main chassis 

82pF 1000V +/-0.05%



Q1 of the RF board.







Extender Cards

These are pictures of original Yaesu Extender cards kindly supplies by Kendwell AB1JZ.  I have been looking into making these boards.  The boards will not be anything special but will get the job done at minimal cost for a set.

IMGP0220.JPG (1612260 bytes) IMGP0221.JPG (1491443 bytes) IMGP0222.JPG (1511339 bytes) IMGP0223.JPG (1461527 bytes) IMGP0224.JPG (1554426 bytes)
IMGP0225.JPG (1308185 bytes) IMGP0226.JPG (1430277 bytes) IMGP0227.JPG (7053 bytes) IMGP0228.JPG (14504 bytes) IMGP0229.JPG (18571 bytes)
IMGP0230.JPG (23993 bytes) IMGP0231.JPG (22546 bytes)      


scan0001.gif (329995 bytes)This is an 18 pin extender that I cobbled together from an old relay board and a surplus card edge connector.  It helped me troubleshoot the PB-1811 RF board.  It may not be pretty but it works. 



Here are some numbers for edge connectors.  A 15 pin connector can be used for the 14 pin boards.  Just shift the board over to one side.  Put an insert or key in the 15th position of the female connector.


Product Detail
Order Qty.
(USD) as of 2009 

Ships Now
$4.52 $4.52
Ships Now
$3.72 $3.72

Ships Now
$4.66 $4.66

Ships Now
$2.44 $2.44
For additional information on availability, click on the Mouser Part #.
 $15.34 (USD)


Here are the files I created with a particular PCB board manufacturer's free software.  I found this manufacturer in Nuts and Volts magazine.  I have done no business with them so you are on your own.

The free software from www.expresspcb.com is needed to open the files below.  My copy of MS Explorer is changing the extension to "html".   If this happens to you change the extension back to  "pcb".  I am not sure why this happens with MS and not with Google Chrome.  Go figure.....


Theses images were  "printed" from the below files.  (Not to scale.) wpe65.gif (11581 bytes) Image "printed" from the below file.. wpe5F.gif (13915 bytes) wpe61.gif (18095 bytes) wpe63.gif (21594 bytes)
These files are the working ExpressPCB application files or source files.  10 pin card  work file. 14 pin card with 15 pin connector. 18 pin card 22 pin card


These are my rough calculations:


Cost to make a set (4) of Extender cards using; Express PCB and Mouser (2009)

SETS of 4 4 20 25 50 100  
card edge connectors $72.00 $310.00 $334.00 $621.00 $1,161.00 Mouser
10 pin PC $91.09 $131.00 $156.00 $238.00 $397.00 ExpressPCB
14 pin pc $93.55 $212.00 $255.00 $430.00 $792.00 ExpressPCB
18 pin pc $99.83 $244.00 $296.00 $511.00 $952.00 ExpressPCB
22 pin pc $105.95 $270.00 $333.00 $577.00 $1,086.00 ExpressPCB
Initial investment $462.42 $1,167.00 $1,374.00 $2,377.00 $4,388.00  
Cost per set of 4 cards $115.61 $58.35 $54.96 $47.54 $43.88  




I ordered a set of Extender boards from BAS.  They arrived from Holland with in a week or 10 days!  I am impressed.  He gave me a great price compared with my research above, and all other offers I heard to date.  I will pick up a set of card edge connectors from Mouser with my next parts order.  

There was a bit of confusion.  BAS sells complete extender boards with connectors. Please contact him directly, via email below, for costs.  I asked BAS what I should post for him.  Below is his September 23, 2009 answer.

Thanks Paul,

Complete set is $125 as I emailed you before. I got a bunch of emails from various countries to ask for bare boards but I've also seen the Ebay listings of extender boards and I don't want people to sell my boards for a lot of money. They are tools and have to be used to repair and restore various rigs for the amateur. It is still hobby for me as well!




BAS said, "The boards are made with Eagle and are exact on the .156" grid."  

I have an other 101 restoration/Elmer at the Skyview Radio Club coming up. A member has one to get back on the air!   These are not collector or original Yaesu board but will do quit fine for my application.


I scanned these boards.

BASboardsfront.gif (481629 bytes)    

 Click to enlarge, they look better bigger.

BASboardsBack.gif (374618 bytes)

The 10 pin is double sided.  The other three have traces on one side only.

BAS's contact information is:  Temporarily removed.     

Good luck and happy boarding! Surf's up baby!  

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