Hello all,
Hope I can get some sage advice on the alignment of a Hallicrafters S-76 receiver. For each of the band segments there are 3 to 4 adjustments. Mostly trimmer caps. All of the adjustments interact with each other. If I turn one then the others go way off. My question is, is there a standard starting position for all the trimmers? To start, should you set them all to max capacity (clockwise)and start from there, or do you start with all trimmers in min capacity (clockwise). How about the starting points for inductors. The reason I am asking is that the previous owner tried to fix problems by turning everything that had a screwdriver adjust! Therefore, the current settings are not even close and can't be peaked with a slight adjustment. I must start from scratch like it just came off the assembly line and hit the test department for the first time.
Thanks for any advice.
Dean

Hi, Dean. Have you fished around on the BAMA site for alignment instructions? http://bama.sbc.edu/

That site has limited bandwidth, particularly during the day, so I wasn't able to look at anything. You might have to go with a manual for a similar Halli model.

I think BAMA increases the number of web connections after some time in the evening, perhaps 9 or 10pm EST?

Hi Doug,
Yes, I have the manual but it does not mention anything about presetting the trimmers before alignment. I believe the manual writers assume that the radio has not been messed with and should therefore be "close" as far as alignment goes. The sister site of Bama, (bama.edebris.com) takes more FTP connections. That is the site I use for the manuals.

:Hi, Dean. Have you fished around on the BAMA site for alignment instructions? http://bama.sbc.edu/
:
:That site has limited bandwidth, particularly during the day, so I wasn't able to look at anything. You might have to go with a manual for a similar Halli model.
:
:I think BAMA increases the number of web connections after some time in the evening, perhaps 9 or 10pm EST?

I just did an S85 so I can appreciate your problems. Here is an improved procedure for your S-76:

Band 4:
1. Adjust Trimmer A (C46) for a peak at 30Mhz.
2. Ajust slug D (L11) for a peak at 14 Mhz
3. Repeat 1 and 2 as many times as needed until
both settings are correct.
4. Adjust trimmers B (C37) and C (C3) for peaks at 30Mhz.
5. Adjust slugs E (L8) and F (L1) for peaks at 14Mhz.

Band 3:
1. Adjust Trimmer G (C49) for a peak at 11.5 Mhz.
2. Ajust slug K (L12) for a peak at 5.1 Mhz
3. Repeat 1 and 2 as many times as needed until
both settings are correct.
4. Adjust trimmers H (C39) and J (C4) for peaks at 11.5 Mhz.
5. Adjust slugs L (L9) and M (L2) for peaks at 5.1 Mhz.

Band 2:
1. Adjust Trimmer N (C51) for a peak at 4.6 Mhz.
2. Ajust slug R (L13) for a peak at 1.925 Mhz
3. Repeat 1 and 2 as many times as needed until
both settings are correct.
4. Adjust trimmers P (C40) and Q (C5) for peaks at 4.6 Mhz.

Band 1:
1. Adjust Trimmer S (C53) for a peak at 1.4 Mhz.
2. Ajust Trimmer V (C54) for a peak at .6 Mhz
3. Repeat 1 and 2 as many times as needed until
both settings are correct.
4. Adjust trimmers T (C43) and U (C6) for peaks at 1.4 Mhz.

Done!

It takes a bunch of back and forth on steps 1 and 2 of each band to get it done.

Tony

:Hi Doug,
: Yes, I have the manual but it does not mention anything about presetting the trimmers before alignment. I believe the manual writers assume that the radio has not been messed with and should therefore be "close" as far as alignment goes. The sister site of Bama, (bama.edebris.com) takes more FTP connections. That is the site I use for the manuals.
:
:
::Hi, Dean. Have you fished around on the BAMA site for alignment instructions? http://bama.sbc.edu/
::
::That site has limited bandwidth, particularly during the day, so I wasn't able to look at anything. You might have to go with a manual for a similar Halli model.
::
::I think BAMA increases the number of web connections after some time in the evening, perhaps 9 or 10pm EST?

Hi Tony,
Thank you so much for the info. Your procedure includes the same trimmers as called out for in the manual but in a slightly different order. I will try it out. The circuit design seems a bit odd in the way the trimmers interact but once set I guess they should be great. Thanks again!

:I just did an S85 so I can appreciate your problems. Here is an improved procedure for your S-76:
:
:Band 4:
: 1. Adjust Trimmer A (C46) for a peak at 30Mhz.
: 2. Ajust slug D (L11) for a peak at 14 Mhz
: 3. Repeat 1 and 2 as many times as needed until
: both settings are correct.
: 4. Adjust trimmers B (C37) and C (C3) for peaks at 30Mhz.
: 5. Adjust slugs E (L8) and F (L1) for peaks at 14Mhz.
:
:Band 3:
: 1. Adjust Trimmer G (C49) for a peak at 11.5 Mhz.
: 2. Ajust slug K (L12) for a peak at 5.1 Mhz
: 3. Repeat 1 and 2 as many times as needed until
: both settings are correct.
: 4. Adjust trimmers H (C39) and J (C4) for peaks at 11.5 Mhz.
: 5. Adjust slugs L (L9) and M (L2) for peaks at 5.1 Mhz.
:
:Band 2:
: 1. Adjust Trimmer N (C51) for a peak at 4.6 Mhz.
: 2. Ajust slug R (L13) for a peak at 1.925 Mhz
: 3. Repeat 1 and 2 as many times as needed until
: both settings are correct.
: 4. Adjust trimmers P (C40) and Q (C5) for peaks at 4.6 Mhz.
:
:Band 1:
: 1. Adjust Trimmer S (C53) for a peak at 1.4 Mhz.
: 2. Ajust Trimmer V (C54) for a peak at .6 Mhz
: 3. Repeat 1 and 2 as many times as needed until
: both settings are correct.
: 4. Adjust trimmers T (C43) and U (C6) for peaks at 1.4 Mhz.
:
:
:Done!
:
:It takes a bunch of back and forth on steps 1 and 2 of each band to get it done.
:
:Tony
:
:
:
:
:
::Hi Doug,
:: Yes, I have the manual but it does not mention anything about presetting the trimmers before alignment. I believe the manual writers assume that the radio has not been messed with and should therefore be "close" as far as alignment goes. The sister site of Bama, (bama.edebris.com) takes more FTP connections. That is the site I use for the manuals.
::
::
:::Hi, Dean. Have you fished around on the BAMA site for alignment instructions? http://bama.sbc.edu/
:::
:::That site has limited bandwidth, particularly during the day, so I wasn't able to look at anything. You might have to go with a manual for a similar Halli model.
:::
:::I think BAMA increases the number of web connections after some time in the evening, perhaps 9 or 10pm EST?

This is just for the RF alignment. You do the IF alignment first as shown in the manual.

You will notice that you are tweaking the capacitor on one end of the band and the inductor on the other in steps 1 and 2. These are the oscillator adjustments. The idea is to tweak it so that the inductor value is just right to give proper tracking from one end of the dial to the other.

The low band uses a series capacitor instead of adjusting the inductor to accomplish the same thing.

The step 4 and 5 adjustments are for the antenna and mixer coils. These do not have the strong interaction of steps 1 and 2. If you look up the inductors in the parts lists, you can see what each one is for. The trimmer caps are also spelled out in the parts list but not as well in some cases. To be sure which is which, look at the schematic and see which inductor the capacitor goes with and then look up the inductor in the parts list.