Yaesu FT-102 Suggestions

Modified 12-8-2008 - see color below @ CW transmit and other additional comments

Suggestions to get the best out of your FT-102

Shift and Width Controls:

The shift and width controls are intended to suit your personal preference by giving you the ability to customize the sound of your rig and minimize interference. The gray zone on the controls represents the width of your passband. Turning both controls at once via the friction lock, either clockwise or counterclockwise, shifts your passband but does not change your bandwidth. The gray area remains the same size. Both filter slopes move in tandem. This is used when you want to eliminate interference that is only on one side of the signal that you are listening to as it gives you two filter slopes that reinforce each other (one from each of the two IF filters) as rejection fighting devices. (First three photos)

   If you rotate one control against the other, the gray area will become smaller = narrowing of the passband width. (See photos 4,5,and 6 below). One edge on the control will be a chrome gray border and the other border will be a gray against black border. This is used to reduce interference from simultaneously transmitted signals where one is above your frequency of interest and the other is below. In this instance one filter's edge is used on one side and the other filter's edge is used on the opposite side. The chrome against gray border is the effect of the 8.2 MHz filter and the gray against black is the 455 KHz filter edge. When the gray area is at its widest (chrome to gray borders at both sides) both filter edges are coincident and the passband of each is the same and they reinforce each other.

   You may find that certain combinations of rotation of each of the friction locked controls to be pleasing to your ears. This is then the way the control should be set for you. There is no law that states that both controls must be centered and vertical.

If you adjust this double ganged friction dual control for the three above variables (pleasant sound, interference rejection to one side or interference rejection on both sides of your passband) you will begin to realize the potential of your FT-102 and why this control format is the best around. I can't begin to tell you how many hams don't understand the concept of the triple function of this control. There is nothing else like it in ham radio as the control of these functions in other radios takes two to three separate controls and you have to toggle back and forth between those. By the time you get it right wth two separate controls your station has stopped transmitting.

I believe this misconception stems from the instruction manual which is not very clear on the usage of the control. With all of this in mind, let this control become an extension of your brain and ears. Learn how to manipulate it with your thumb, pointer, middle finger and wrist of one hand (all three functions at once) like playing a musical instrument. After some practice and getting used to the adjustment procedure you will find every other type of radio awkward and cumbersome to adjust.

One more note here - the controls work differently in USB and LSB so that a clockwise turn on USB produces the same effect as a counterclockwise turn on LSB. The controls are reversed in the opposite sideband.

The digital display:

   Since the digital display in the Yaesu FT-102 is in reality a hybrid frequency counter it is probable that when you are on the border of the next 100 cycle segment there will be a flicker of the last significant digit. This has no effect on the stability of the frequency of the radio and only represents that point where the counter at one counting (updated five times per second) sees either of the two rounded readings and can't quite decide into which number it should place the display. In reality this zone is 4 cycles wide.

   In other radios such as a Kenwood 430 (just as an example) the display number is generated by a divide by function of the computer chip. This display will not change no matter how much drift there is in the operating frequency because it is not a counter but a rather a mathematical number processor. If you adjust the master oscillator frequency in a 430 the radio will change frequency drastically but the display will not move. I personally believe it is better to have a counter so you can observe any drift rather than having the drift be hidden from you (even though you have to put up with the flicker).

The RF amp button:

   If the S meter reads the background noise level at more than an S 5 with the RF amp button depressed (= on) my recommendation is turn the function off (=out) as you don't need the extra sensitivity. If the control is out (= off) the front end is bypassed and the signal goes directly to the first mixer for even better receiver performance. This is the same as the AIP control in Kenwoods and the IPO function in the newer Yaesus.

   On the other hand if the background noise level is less than an S 5 with the control pushed in (=on) then leave it on.

   Sensitivity on 20 meters is usually .15 uV (or better) for 10dB S+N/N with the control pushed in and .6 uV for 10dB S+N/N with it in the out position. If you leave the control depressed when the bandnoise on receive is above S 5 on your S-meter (such as on 80 meters) that noise will be adjusted by the ALC to the same intensity at the speaker as the signal you are listening to. It will therefore make copy more difficult.

Noise Blanker:

   When using the noise blanker with very strong signals nearby or even on a strong station that you are listening to, severe distortion products may be heard. In this instance just turn the level control down and the signal will clear up. A good zone should be obtainable where there is effective reduction of the pulse noise and a good clean copy on your signal of interest. Sometimes I am listening to a very weak station and have the noise blanker turned way up and another station that is strong breaks in. Distortion will be heard so always check to see if the control is engaged and how high the level is set.

Tune up:

   I have included instructions for proper tune up of the radio. Most important here is the rule of "ten on and ten off". This means that the maximum continuous key down time at full output should not exceed ten seconds. And even more important is that in addition you must wait ten to fifteen seconds between key downs. If you don't follow this rule you will be making trouble for yourself and waste money needlessly because you will be exceeding the safe dissipation ability of the tube and the extra heat generated will deform the grid and screen in the 6146s. When the tube has been poisoned in this way you will start to get thermal runaway where the cathode current creeps up and will blow your fuse (watch the IC position of your meter if this happens). Do not replace the fuse with anything larger than a 5 amp quick blow fuse and replace the tubes. Nothing else will effect a cure once the fuses start blowing.

When the tubes have been heat damaged it will take five or ten minutes at first in transmit for the fuse to blow. The times will become shorter as time goes on. If you use a larger fuse or a slow blow fuse, one of two things will happen - The radio will either catch fire or blow the transformer and choke. This course of events is the main reason that FT-102s go to the graveyard.

Although I can repair the resultant damage, the radio usually smells from fire and I cannot undo that or the liquification of the lacquer from the transformer windings which get deposited all over the controls of the local board making adjustment of those controls in the future unreliable. So the radio then goes to the parts graveyard.



SSB TRANSMIT:

   And lastly in SSB, I recommend that you do not run the ALC in transmit above S3 to S5 for best audio clarity. Running the ALC meter into the S9 range acts like a processor and yields 10 dB of compression. It will give you more punch but with some mild loss of quality.



CW TRANSMIT:

   Some of the earlier models of the FT-102 had a problem with Key Clicks on CW. By serial number 050xxx Yaesu had it cleaned up. Let me suggest that when working CW and after you tune the transmitter cut the Drive control back until the ALC no longer comes up off the peg. At the same time make sure you still have maximum power output. It is an easy adjustment with the two meters and the Drive control. This will give you very sweet CW characteristics with beautiful shaping of the leading and trailing edge of your CW note. This will eliminate Key Clicks in the early models and make the later models sound even better.

   If you follow the suggestions above your FT-102 will be the most reliable radio you have ever owned with the only upkeep being tube replacement every five to ten years under heavy usage. You will also get the best performance possible from your rig.

Thanks for looking this over. Enjoy your Yaesu FT-102 and get a hold of me if you need any questions answered (954-961-2034 in the evenings).

   73 de NC4L Mal

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The shift and width controls are intended to suit your personal preference by giving you the ability to customize the sound of your rig and minimize interference. The gray zone on the controls represents the width of your passband. Turning both controls at once via the friction lock, either clockwise or counterclockwise, shifts your passband but does not change your bandwidth. The gray area remains the same size. Both filter slopes move in tandem. This is used when you want to eliminate interference that is only on one side of the signal that you are listening to as it gives you two filter slopes that reinforce each other (one from each of the two IF filters) as rejection fighting devices. (First three photos)

If you rotate one control against the other, the gray area will become smaller = narrowing of the passband width. (See photos 4,5,and 6 below). One edge on the control will be a chrome gray border and the other border will be a gray against black border. This is used to reduce interference from simultaneously transmitted signals where one is above your frequency of interest and the other is below. In this instance one filter's edge is used on one side and the other filter's edge is used on the opposite side. The chrome against gray border is the effect of the 8.2 MHz filter and the gray against black is the 455 KHz filter edge. When the gray area is at its widest (chrome to gray borders at both sides) both filter edges are coincident and the passband of each is the same and they reinforce each other.

You may find that certain combinations of rotation of each of the friction locked controls to be pleasing to your ears. This is then the way the control should be set for you. There is no law that states that both controls must be centered and vertical.

If you adjust this double ganged friction dual control for the three above variables (pleasant sound, interference rejection to one side or interference rejection on both sides of your passband) you will begin to realize the potential of your FT-102 and why this control format is the best around. I can't begin to tell you how many hams don't understand the concept of the triple function of this control. There is nothing else like it in ham radio as the control of these functions in other radios takes two to three separate controls and you have to toggle back and forth between those. By the time you get it right wth two separate controls your station has stopped transmitting.

I believe this misconception stems from the instruction manual which is not very clear on the usage of the control. With all of this in mind, let this control become an extension of your brain and ears. Learn how to manipulate it with your thumb, pointer, middle finger and wrist of one hand (all three functions at once) like playing a musical instrument. After some practice and getting used to the adjustment procedure you will find every other type of radio awkward and cumbersome to adjust.

One more note here - the controls work differently in USB and LSB so that a clockwise turn on USB produces the same effect as a counterclockwise turn on LSB. The controls are reversed in the opposite sideband.

Since the digital display in the Yaesu FT-102 is in reality a hybrid frequency counter it is probable that when you are on the border of the next 100 cycle segment there will be a flicker of the last significant digit. This has no effect on the stability of the frequency of the radio and only represents that point where the counter at one counting (updated five times per second) sees either of the two rounded readings and can't quite decide into which number it should place the display. In reality this zone is 4 cycles wide.

In other radios such as a Kenwood 430 (just as an example) the display number is generated by a divide by function of the computer chip. This display will not change no matter how much drift there is in the operating frequency because it is not a counter but a rather a mathematical number processor. If you adjust the master oscillator frequency in a 430 the radio will change frequency drastically but the display will not move. I personally believe it is better to have a counter so you can observe any drift rather than having the drift be hidden from you (even though you have to put up with the flicker).

If the S meter reads the background noise level at more than an S 5 with the RF amp button depressed (= on) my recommendation is turn the function off (=out) as you don't need the extra sensitivity. If the control is out (= off) the front end is bypassed and the signal goes directly to the first mixer for even better receiver performance. This is the same as the AIP control in Kenwoods and the IPO function in the newer Yaesus.

Sensitivity on 20 meters is usually .15 uV (or better) for 10dB S+N/N with the control pushed in and .6 uV for 10dB S+N/N with it in the out position. If you leave the control depressed when the bandnoise on receive is above S 5 on your S-meter (such as on 80 meters) that noise will be adjusted by the ALC to the same intensity at the speaker as the signal you are listening to. It will therefore make copy more difficult.

When using the noise blanker with very strong signals nearby or even on a strong station that you are listening to, severe distortion products may be heard. In this instance just turn the level control down and the signal will clear up. A good zone should be obtainable where there is effective reduction of the pulse noise and a good clean copy on your signal of interest. Sometimes I am listening to a very weak station and have the noise blanker turned way up and another station that is strong breaks in. Distortion will be heard so always check to see if the control is engaged and how high the level is set.

I have included instructions for proper tune up of the radio. Most important here is the rule of "ten on and ten off". This means that the maximum continuous key down time at full output should not exceed ten seconds. And even more important is that in addition you must wait ten to fifteen seconds between key downs. If you don't follow this rule you will be making trouble for yourself and waste money needlessly because you will be exceeding the safe dissipation ability of the tube and the extra heat generated will deform the grid and screen in the 6146s. When the tube has been poisoned in this way you will start to get thermal runaway where the cathode current creeps up and will blow your fuse (watch the IC position of your meter if this happens). Do not replace the fuse with anything larger than a 5 amp quick blow fuse and replace the tubes. Nothing else will effect a cure once the fuses start blowing.

When the tubes have been heat damaged it will take five or ten minutes at first in transmit for the fuse to blow. The times will become shorter as time goes on. If you use a larger fuse or a slow blow fuse, one of two things will happen - The radio will either catch fire or blow the transformer and choke. This course of events is the main reason that FT-102s go to the graveyard.

Although I can repair the resultant damage, the radio usually smells from fire and I cannot undo that or the liquification of the lacquer from the transformer windings which get deposited all over the controls of the local board making adjustment of those controls in the future unreliable. So the radio then goes to the parts graveyard.

And lastly in SSB, I recommend that you do not run the ALC in transmit above S3 to S5 for best audio clarity. Running the ALC meter into the S9 range acts like a processor and yields 10 dB of compression. It will give you more punch but with some mild loss of quality.

Some of the earlier models of the FT-102 had a problem with Key Clicks on CW. By serial number 050xxx Yaesu had it cleaned up. Let me suggest that when working CW and after you tune the transmitter cut the Drive control back until the ALC no longer comes up off the peg. At the same time make sure you still have maximum power output. It is an easy adjustment with the two meters and the Drive control. This will give you very sweet CW characteristics with beautiful shaping of the leading and trailing edge of your CW note. This will eliminate Key Clicks in the early models and make the later models sound even better.

If you follow the suggestions above your FT-102 will be the most reliable radio you have ever owned with the only upkeep being tube replacement every five to ten years under heavy usage. You will also get the best performance possible from your rig.