Aligning - Tuning Yaesu 101E

[Rudes]

Boy do I have a headache! I am not an expert tech but have built many kits & I know how to read and use an VOM. I am using the Yaesu manual and trying to get the rig working like it should. When starting at band 10D as per the manual I can tune and get 60rms and 120 pep output on ssb on my watt meter by adjusting slug 102 & 103. When moving on to the 10A band I get practically nothing. I checked the white wires on the trap coil & selector contacts and they seem ok. It seems that when I move from whatever frequency that I tuned on the power drops significantly. Am I doing something wrong...is there an easier way? Thanks...

 

[Doc Feelgood]

Have you checked the bandswitch itself?

 

[Shockwave]

You may not like this answer however, if your goal is a correct alignment to restore normal operation on all bands, you may be getting farther away then closer without the proper test equipment and experience. The slugs on the preselector track linearly on each band. The trimmer caps on the bottom of the radio align the individual bands. Changing the location of the slugs is likely to make one band work, at the expense of all the others and will reduce receiver sensitivity if the third slug is not tracking with the two transmit preselector slugs.

 

[wavrider]

Last thread you stated you were getting good power out on the lower bands but low power on the upper bands,

Before you start turning slugs I would reccomend you get those tubes tested on a good tube tester.

Make sure your finals are good would be my first step. Then start an alignment.

The alignment procedure is a step by step process. Each step needs to be followed in sequential order to obtain the best performance from that rig.

I have never had to re align a tuning slug on any of that 101's I have come across the bench. I have had to adjust the tx/rx trimmers under the chassis.

Those old 101's have been around so long that it is almost guaranteed somewhere they have had the screwdriver put to them.

 

[Rudes]

Thanks for the replies so far. I'm now hearing and reading that I never should have turned the 101-102-103 slugs. Meanwhile everyone was telling me to read the service manual and that's the first thing the manual says, is to adjust the slugs on the 10D band and go from there. I will check further to make sure I'm getting good contact on the band selector switch on the 10A band since the power is so low there. I am using another transceiver and frequency counter to aid me. Does anyone know of someone that would be able to tune this up in the N.Y. metro area in case I can't fix it?

 

[dxhound]

Boy do I have a headache! I am not an expert tech but have built many kits & I know how to read and use an VOM. I am using the Yaesu manual and trying to get the rig working like it should. When starting at band 10D as per the manual I can tune and get 60rms and 120 pep output on ssb on my watt meter by adjusting slug 102 & 103. When moving on to the 10A band I get practically nothing. I checked the white wires on the trap coil & selector contacts and they seem ok. It seems that when I move from whatever frequency that I tuned on the power drops significantly. Am I doing something wrong...is there an easier way? Thanks...

Ok, Maybe Im mis-understanding what you wrote here. But, The way you worded this sounds like you tuned the radio using the preselect, plate and loading knobs on band 10D. Then WITHOUT retuning the preselect, load and tune you switch to Band 10A and are now seeing little power out. Is this correct? If this is what you are doing you are wrong. You absolutely have to retune the radio using the 3 knobs listed above every time you change frequency more than 50KHz (10Khz on 80-160)

 

[Rudes]

This is AFTER retuning I'm seeing little to no power on 10A.

 

[Rudes]

Ok - Between working the preselect and TC5 I have good power on all the ten meter bands a,b,c,d, but only on the higher frequencies on the VFO. As you turn the VFO dial in the opposite direction the power takes a dive and you can not adjust with the preselect.

 

[wavrider]

Try looking at the neutralization again to see if it needs re-adjusted due to the re-tuning of the rig.

Sounds like you are making progress.

Also check the bias of the finals.

Keep in mind not to keep that rig keyed for to long as those finals are expensive and fragile.

 

[Rudes]

OK thanks. Planning on replacing the finals when all said and done being that I have no idea how old they are and that the previous owner had GE tubes in it without changing the c125 to 10pf. The tubes are most likely on the weak side but it does not explain why the rig tunes well on the higher side of any band than the lower?

 

[HiDef]

Not saying this is the problem but.

I remembered hearing about resistors across the 10 meter driver and maybe even other stages ganged to the driver tuning tank circuits used for lowering Q.

If those go open it might tune up fine somewhere but not across the whole 500 khz.

 

[Rudes]

Thanks! Do you know what board those resistors would be on? The trans & receive are much better on one end of the dial than the other.

 

[Shockwave]

It sounds like the bandpass filter is misaligned. The output of the VFO passes through this bandpass filter on it's way to the mixer unit. It's job is to remove all of the harmonic content the VFO would generate before it's signal is used.

To confirm this is the problem, the easiest thing to do is see if the receive drops off too. The receive signal also passes through this filter and would be effected similar to the transmit signal. It will also be present on every band as you get them working.

 

[Rudes]

This appears to be the problem. Any idea on how to adjust the filter?