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Re: S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!

 

This all just doesn't sound right. Did this receiver EVER work? If
it did its not miswired. If it didn't how did it get through factory
alignment and QC? How did it get sold in the first place? If I
understand the complaint correctly half the broadcast band does not
work. That is a very big failure. This was a medium low priced receiver,
on the order of $90 when new. Not a cheap set and not a toy. In general
Hallicrafters did not make junk (with some exceptions) and usually
offered good value if not world class performance.
The comments about recieivers with antanna trimmers is just not
correct. Generally the trimmer or compensator is there to allow the use
of a variety of antennas while the lack of a trimmer means the input
wants something close to the impedance presented by the dummy antenna
prescribed. Generally, these receivers were meant to work from poor
antennas especiallay at the MF broadcast band, a couple of feet of wire
should be enough for local stations. It is certainly not going to be so
critical that the set won't work over half the band.
We are being led to believe that Hallicrafters design engineers
didn't know what they were doing and that their production engineers
didn't either. That no one on the line ever came to their supervisor
saying the set would not work over part of its range.
It IS possible for the schematic to be wrong. This is not what the
sets were build from, but what is in the set should work.
What is going on here?


On 2/9/2025 9:55 AM, Emanuele Girlando via groups.io wrote:
Guys,
one of the reasons I wants to give up with this one is the poor design
in the ANT RF circuitry.

--
Richard Knoppow
Los Angeles
WB6KBL
SKCC 19998
Re: Page

 

?
Thanks Larry! I really appreciate it. Our domestic and International clients seem to grow every day. Vintage HI-Fi restoration also seems to be hot.
?
Pete, wa2cwa
?
?
On Sat, 8 Feb 2025 23:57:51 +0000 (UTC) "Larry Knapp via groups.io" <kc8jx@...> writes:

Pete - I have ordered several manual reprints via your company.? I find the product to be just as good (if not better) than an original.? The Heathkit manuals are sort of a benchmark for me and your reprints definitely are high quality.?? I hope you continue to provide this service for us hams and all the other clients you may have.? 73, Larry KC8JX

?
Re: S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!

 

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Emanuele, no need to reply to this, it is more for others that have an S-85. I don’t blame you for being fed-up with this radio, and giving up; we all have had that feeling, ?but for the benefit of others we wonder if ?yours is wired as per the schematic, or is it actually wired like I suggested it should be. You seem to be very good at tackling all this stuff, so if the wiring is apparently wrong at R65, you no doubt changed it and tried it again, I would think but I saw no comment on that point.

?

I don’t have an S-85, but, for any others with an S-85: does it have the same alignment problem?, and poor sensitivity below 1Mc? ….and is it wired as per the schematic? as I highlighted before? ?I don’t believe they BUILD them using a schematic, instead they use a more practical physical wiring drawing; so it is hard to believe that they went out the door wired, and working incorrectly, but I have seen worse cases when I was in industrial electronics manufacturing, so impossible things do happen, then I had to find and fix the impossible out in the field. The big boss says “ship it anyhow”, and QA ?succumbs.

Emanuele mentioned the S-99 is an exact copy in some detailed respects, so I looked and found that the S-99 eliminates all capacitors for the 1st RF tanks and the slugs for bands 3,4.? ?It is interesting that? they still list C3 with L3, but C3 itself has vanished.. ???typical copy and paste draughting [drafting if you’re in USA] ??

?

From: [email protected] [mailto:[email protected]] On Behalf Of Emanuele Girlando via groups.io
Sent: Sunday, February 9, 2025 12:56 PM
To: [email protected]
Subject: Re: [HallicraftersRadios] S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!

?

Guys,

one of the reasons I wants to give up with this one is the poor design in the ANT RF circuitry.

I noticed the schematic diagram anomalies, both the 1&2 bands wiring error and the fancy S1A-REAR layout, at the same time as Don did. I was shocked and disappointed by that.

Days ago, while approaching the refurbishing project of my S-85, I did read that the SX-99 is a S-85 plus IF-XTAL and S-Meter. So I download the SX-99 schematic diagram to compare with but I discovered:

1.???? the 1&2 bands wiring error and the fancy S1A-REAR layout are? exactly the same in SX-99 as in S-85; that was shocking and disappointing for the second time (!!).

2.???? the ANT RF circuitry design has been completely reviewed in SX-99 eliminating TRIMCAPs and introducing a more useful antenna trimmer you can adjust while switching between? bands and/or connecting different antenna types input socket.

My conclusion was that the S-85 ANT circuit doesn't worth any additional effort to be understood or further analyzed: The Hallicrafters it self changed its design in successive projects..

Furthermore, IMHO, there is no point in having a ANT tuned circuit inside the radio when, in everyday use, you would have to retune it every time you change bands or the type of antenna connected to the radio. Consequently? I got the conclusion that leaving it as "wide" as possible sounds like a good choice.

?

In the hope of modifying my S-85 by reproducing the solution found in the SX-99, I also checked if the coils part numbers were the same but, unfortunately, they are not.

?

The only remaining test I want to do on this one is to align ANT and MIX RF stages with the chassis inside the cabinet.

In other words I want to check if the service manual statement:

?

?

should be read as: "RF alignment MUST be made with chassis in the cabinet. ...".

?

Thank you all once again.

--

Emanuele (IU1KNR).


--
don??? va3drl
Re: S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!

 

Guys,
one of the reasons I wants to give up with this one is the poor design in the ANT RF circuitry.
I noticed the schematic diagram anomalies, both the 1&2 bands wiring error and the fancy S1A-REAR layout, at the same time as Don did. I was shocked and disappointed by that.
Days ago, while approaching the refurbishing project of my S-85, I did read that the SX-99 is a S-85 plus IF-XTAL and S-Meter. So I download the SX-99 schematic diagram to compare with but I discovered:
  1. the 1&2 bands wiring error and the fancy S1A-REAR layout are? exactly the same in SX-99 as in S-85; that was shocking and disappointing for the second time (!!).
  2. the ANT RF circuitry design has been completely reviewed in SX-99 eliminating TRIMCAPs and introducing a more useful antenna trimmer you can adjust while switching between? bands and/or connecting different antenna types input socket.
My conclusion was that the S-85 ANT circuit doesn't worth any additional effort to be understood or further analyzed: The Hallicrafters it self changed its design in successive projects..
Furthermore, IMHO, there is no point in having a ANT tuned circuit inside the radio when, in everyday use, you would have to retune it every time you change bands or the type of antenna connected to the radio. Consequently? I got the conclusion that leaving it as "wide" as possible sounds like a good choice.
?
In the hope of modifying my S-85 by reproducing the solution found in the SX-99, I also checked if the coils part numbers were the same but, unfortunately, they are not.
?
The only remaining test I want to do on this one is to align ANT and MIX RF stages with the chassis inside the cabinet.
In other words I want to check if the service manual statement:
?
?
should be read as: "RF alignment MUST be made with chassis in the cabinet. ...".
?
Thank you all once again.
--
Emanuele (IU1KNR).
Re: S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!

 
Edited

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Maynard, the arrows inside the wafers do the trick for me, together with the “shown in band 4 position” general note.

One of my first obstacles was understanding the first wafer; it was mucking me up.

End image

From: [email protected] [mailto:[email protected]] On Behalf Of Maynard Wright via groups.io
Sent: Saturday, February 8, 2025 3:35 PM
To: [email protected]
Subject: Re: [HallicraftersRadios] S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!

?

Another interesting thing about the diagram: The S-40B diagram has
"(FRONT)" and "(REAR)" but not "(FRONT) VIEWED FROM REAR" as for the
S-85. The S-40B diagram does show both clockwise and counterclockwise
rotations as does the S-85.

For the rotation to be correct when both counterclockwise and clockwise
directions are specified, the two sides of the wafer must be viewed from
different directions, the "FRONT" presumably from the front and the
"REAR" presumably from the rear.

Just be careful to keep track of which contacts are in use for a
particular position of the switch.

73,

Maynard
W6PAP


--
don??? va3drl
Re: Missing page S2001A

 

Pete - I have ordered several manual reprints via your company.? I find the product to be just as good (if not better) than an original.? The Heathkit manuals are sort of a benchmark for me and your reprints definitely are high quality.?? I hope you continue to provide this service for us hams and all the other clients you may have.? 73, Larry KC8JX

On Thursday, February 6, 2025 at 08:31:21 PM EST, Peter A Markavage via groups.io <pmarkavage@...> wrote:


Thanks Pete. I appreciate the complement.
?
I find it very gratifying that my work helps someone bring a piece of equipment back to life. It also provides me with the joyful option of bringing a possibly bug invested, stored in a garage or basement for 50 of 60 years into a worthwhile and useful document that others can read, use and enjoy.
?
Of course, one can find poorly scanned, incomplete, and highly marked up pages all over the Internet, but even when printed, crap is crap, and stuff is always lost in the transition.
?
I just finished a military manual for a customer. Roughly 200 pages but easy to do even though every page, because of age, was brown. My machine can remove background paper color. But the hicker and hard part, were the five schematics. They were 14 inches high and 52 inches wide. And I decided these were to be done full size. A customer never has to assemble and tape any of my manual pages.
?
This entire project started back in the mid 90's as a bonding project between father and son. Son was in his second high school year but didn't seem to have any idea about his future life endeavors. Since I was dragging boatanchors home to repair and get up and running,?from every hamfest I went to, my collection of manuals for this stuff started to become a pain to manage.? My son created database to manage all the manuals that I also kept collecting. He also suggested creating a catalog booklet, advertising in Electric Radio and a few other publications, and send out the catalog to all interested parties.? I firmly believe this gave him a sense of business activities and helped firm up (or at least give direction) to his future. He also created my first web site and credit him for giving it its name.
?
After? high school he worked for a year before applying and being accepted at Boston Bible College at Hyde Park, MA. He felt he should earn the money to pay for college rather then taking it for granted. For 3 summers while in his college years, he worked at Lucent Technologies as a contractor and used the money earned for tuition.
?
My apologies to the group for rambling, but I'm very proud of my son. I gave him a license manual when he was around seven. When he turned around 27, he finally found the time to become KB1JTP.
?
Pete, wa2cwa
?
?
?
On Thu, 6 Feb 2025 12:50:53 +0000 (UTC) "peteradio@... via groups.io" <peteradio@...> writes:

Pete,

As a loyal customer of yours, who has purchased numerous manuals from you,over the decades, I find your quality, pricing and delivery outstanding!

Keep up the good work and thanks for all the free advice you have provided,and continue to provide, to the amateur community regarding vintage gear!

73's

Pete

W8AA
Re: S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!

 

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Hi Maynard? , this was my posting not the OP Emanuele’s but I will convey my understanding.

First off: this is one manual version or copy. Perhaps there are others that look correct.. And/or there could have been an addendum issued ?with each radio manual. Hoonoes???

Secondly, Emanuele’s ?actual radio might be wired OK.

Emanuele did indicate that bands 3 ?and 4 were very good, but 1 and 2 suffered ?badly in the low half.

Your reasoning about this is as good as any IMO .???

?

I was asking before if L3 is physically one coil form with 2 separate windings, which it seems to be; and like you say would likely have stray coupling magnetically.

The second wafer shorts out? the “other not in use” coils, ?but ?the closeness of band 1 and 2 ??may well allow some coupling. In all probability this is just a drawing error, but somebody might have fixed It to match a drawing??? ???



?

From: [email protected] [mailto:[email protected]] On Behalf Of Maynard Wright via groups.io
Sent: Saturday, February 8, 2025 3:14 PM
To: [email protected]
Subject: Re: [HallicraftersRadios] S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!

?

I agree that the lefthand diagram seems wrong. Note the arrows that
show rotation in opposite directions to synchronize the contacts on the
wafer as you view each side of the wafer.


It seems to me that the lefthand diagram would leave the RF path open on
bands 1 and 2. I think that you wrote that you listened to all of the
bands successfully. If I am correct in that, maybe there is a stray
coupling path around the input tuned circuits that couples enough RF to
make the receiver usable, maybe with the AVC raising the overall gain
quite a bit or with the AVC disabled.

73,

Maynard
W6PAP


--
don??? va3drl
Re: S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!

 

Another interesting thing about the diagram: The S-40B diagram has
"(FRONT)" and "(REAR)" but not "(FRONT) VIEWED FROM REAR" as for the
S-85. The S-40B diagram does show both clockwise and counterclockwise
rotations as does the S-85.

For the rotation to be correct when both counterclockwise and clockwise
directions are specified, the two sides of the wafer must be viewed from
different directions, the "FRONT" presumably from the front and the
"REAR" presumably from the rear.

Just be careful to keep track of which contacts are in use for a
particular position of the switch.

73,

Maynard
W6PAP


On 2/7/25 19:27, don Root wrote:
**

Emanuele and all

This is from BAMA for mark 1A and 1B? and makes no sense to me, ???so I
rewired it at the right.

What say you all?? Do you go with Halligans version?

Don ?end


--
don??? va3drl
Re: S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!

 

I agree that the lefthand diagram seems wrong. Note the arrows that
show rotation in opposite directions to synchronize the contacts on the
wafer as you view each side of the wafer.

It seems to me that the lefthand diagram would leave the RF path open on
bands 1 and 2. I think that you wrote that you listened to all of the
bands successfully. If I am correct in that, maybe there is a stray
coupling path around the input tuned circuits that couples enough RF to
make the receiver usable, maybe with the AVC raising the overall gain
quite a bit or with the AVC disabled.

73,

Maynard
W6PAP


On 2/7/25 19:27, don Root wrote:
**

Emanuele and all

This is from BAMA for mark 1A and 1B? and makes no sense to me, ???so I
rewired it at the right.

What say you all?? Do you go with Halligans version?

Don ?end


--
don??? va3drl
Re: Website Anniversary

 

Thank you, Bill! This site has been very helpful to me.

73,

Maynard
W6PAP


On 2/8/25 06:54, Donald J via groups.io wrote:
Great site - thank you Bill!

On Fri, Feb 7, 2025 at 5:52?PM waltcates via groups.io
<> <cateswa@...
<mailto:[email protected]>> wrote:

*Thank you, Bill!*
*
*
*
*
*Walt Cates, **WD0GOF*
*_ <> _*

*A majority of acceptance is not proof of correctness. *

*
<>**
*

------------------------------------------------------------------------
*From:* [email protected]
<mailto:[email protected]>
<[email protected]
<mailto:[email protected]>> on behalf of Bill (Group
Owner) via groups.io <>
<k2wh@... <mailto:[email protected]>>
*Sent:* Friday, February 7, 2025 1:29 PM
*To:* [email protected]
<mailto:[email protected]>
<[email protected] <mailto:[email protected]>>
*Subject:* [HallicraftersRadios] Website Anniversary
Well believe it or not, its been 20 years, this site has been active
and strong for Hallicrafters Radios.
Started in 2005 as a lark, I am amazed we now have 1,075 members.
With thanks to all our Hallicrafters Experts on this site and they
are experts for sure.e
Regards, and have fun.


*K2WH
Bill's QRZ Biography <>
*
Re: Website Anniversary

 

Thanks Bill, you have done a great job over seeing the site.
Skip Magnuson W7WGM
Re: Website Anniversary

 

Great site - thank you Bill!


On Fri, Feb 7, 2025 at 5:52?PM waltcates via <cateswa=[email protected]> wrote:
Thank you, Bill!


Walt Cates, WD0GOF
?
A majority of acceptance is not proof of correctness.


From: [email protected] <[email protected]> on behalf of Bill (Group Owner) via <k2wh=[email protected]>
Sent: Friday, February 7, 2025 1:29 PM
To: [email protected] <[email protected]>
Subject: [HallicraftersRadios] Website Anniversary
?
Well believe it or not, its been 20 years, this site has been active and strong for Hallicrafters Radios.
?
Started in 2005 as a lark, I am amazed we now have 1,075 members.
?
With thanks to all our Hallicrafters Experts on this site and they are experts for sure.e
?
Regards, and have fun.

K2WH
Re: Website Anniversary

 
Edited

Took me a while to get here but I am happy to be a member of this group.? Thanks you!
Bob
WB9RHW?
Re: S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!

 
Edited

开云体育

?

Emanuele and all

This is from BAMA for mark 1A and 1B? and makes no sense to me, ???so I rewired it at the right.

What say you all?? Do you go with Halligans version?

Don ?end


--
don??? va3drl
Re: Website Anniversary

 

开云体育

And thank YOU, Walt

Tom Latimer



On 2/7/2025 17:52, waltcates via groups.io wrote:

Thank you, Bill!


Walt Cates, WD0GOF
?
A majority of acceptance is not proof of correctness.


From: [email protected] <[email protected]> on behalf of Bill (Group Owner) via groups.io <k2wh@...>
Sent: Friday, February 7, 2025 1:29 PM
To: [email protected] <[email protected]>
Subject: [HallicraftersRadios] Website Anniversary
?
Well believe it or not, its been 20 years, this site has been active and strong for Hallicrafters Radios.
?
Started in 2005 as a lark, I am amazed we now have 1,075 members.
?
With thanks to all our Hallicrafters Experts on this site and they are experts for sure.e
?
Regards, and have fun.

K2WH
Re: Website Anniversary

 

开云体育

Bill

Congratulations on the 20th anniversary.....all your work has been appreciated, even by those of us who aren't amateur operators

You certainly have collected a BUNCH of experts

Tom Latimer

And the same to all the people who add support and expertise




On 2/7/2025 14:29, Bill (Group Owner) via groups.io wrote:

Well believe it or not, its been 20 years, this site has been active and strong for Hallicrafters Radios.
?
Started in 2005 as a lark, I am amazed we now have 1,075 members.
?
With thanks to all our Hallicrafters Experts on this site and they are experts for sure.e
?
Regards, and have fun.

K2WH
Re: Website Anniversary

 

开云体育

Thank you, Bill!


Walt Cates, WD0GOF
?
A majority of acceptance is not proof of correctness.


From: [email protected] <[email protected]> on behalf of Bill (Group Owner) via groups.io <k2wh@...>
Sent: Friday, February 7, 2025 1:29 PM
To: [email protected] <[email protected]>
Subject: [HallicraftersRadios] Website Anniversary
?
Well believe it or not, its been 20 years, this site has been active and strong for Hallicrafters Radios.
?
Started in 2005 as a lark, I am amazed we now have 1,075 members.
?
With thanks to all our Hallicrafters Experts on this site and they are experts for sure.e
?
Regards, and have fun.

K2WH
Re: S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!

 

开云体育

Emanuele ???RE I decided to leave it alone, I give up.? ?Don’t do that, the radio is 99.777% ?, just some strange thing left. It’s ok to take a break and let the brain cool down.

I follow your comments again; all very clear.??

In my sleep, it came to mind that the main dial scale must be set properly. You no doubt have checked this, but maybe there was some slippage since then?

So ?maybe there are set screws on the dial scale hub? .. that might slip?

Also, you must know this but, at low frequencies, the RF tanks will tune much narrower, and so a bit of? unwanted offset will knock the signal down greatly.

Why not do a test: instead of setting the RF band 1 trimmers, at 1400 , set them at ?the low end 600,700? ..and see if they [RF1 and mixer tanks] can be tuned down there by turning the trimmers CW, and if it “aligns”, then try the ?real sensitivity at the low end using the antenna.? If it won’t align there, maybe take a scan of the tanks responses at say 600KCs so you can see if they are too high or too low. I hope you understand my wording. Then you might learn if it ?“tunes low” ?all over the band, or one end is low and the other hi. ?Since you have that Fancy HP gadget you must be able the verify the resonant curves of all tanks at the Hi and the Low end of the band{s}. OF course this is not aligning, it is testing ?to find out where things go wrong. ????????

Must be late there by now spero che tu stia dormendo bene

From: [email protected] [mailto:[email protected]] On Behalf Of Emanuele Girlando via groups.io
Sent: Friday, February 7, 2025 4:02 PM
To: [email protected]
Subject: Re: [HallicraftersRadios] S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!

?

Guys,

I performed a complete RF alignment once again.

I used a sig-gen and the SA just as a "receiver" to "see" the LO signal and followed the service manual instructions.

LO was fine in all bands with LO signal higher than the signal by the IF value (452KHz in my case) in all bands but the n. 4 where it was below.

The dials track the sig-gen signal with very low error in all bands.

The ANT and MIX trimcaps of bands 1&2 didn't peak, exactly as before. I had to leave them fully released (lower C) to get the MAX output possible.

During alignment the BS dial knob was fully CW and , I confirm once again, the BS cap had the plates all out (minimum capacity).

The radio performs well in all bands but the lower part of band 1 (<1MHz, as before).

?

I decided to leave it alone, I give up.

?

Thank you very much for your precious support, guys.

Ciao.

Emanuele (IU1KNR).

?

?


--
don??? va3drl
Re: S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!

 

Put it aside but don't give up on it.
How did you decide the IF frequency? When the IF has a crystal
filter the crystal determines the exact IF frequency but when there is
no crystal you just set the signal generator to the frequency defined in
the instructions, nearly always 455 Khz. The signal for aligning the IF
can be injected into the converter tube as per instructions, i.e. pin 8
through a 0.02uF cap. Actually, the IF can usually be aligned by feeding
the 455 signal into the antenna terminals. with the signal frequency at
about the middle of the dial. Set the signal generator for a weak
signal, you want no more signal than will overcome noise. Peak the six
adjustments to tune the IF to exactly 455 Khz and also adjust the BFO to
zero beat (also in the instructions. I don't think being off by a couple
of Khz is causing your problems but you might as well do it correctly. I
would go over the three IF transformers a couple of times to make sure
they are peaked and there is no interaction (should not be).
Now, what is going on here? A second receiver, or the SA, can
listen to the local oscillator. Make a sniffer loop to put over the
converter tube. check its frequency over the range on the broadcast
band. It should be 455 Khz _above_ the signal frequency at all points.
At the lowest frequency, say 540 Khz, the LO should be at 995 Khz. Check
it at three or four points up the dial. It should be reasonably close to
the signal plus 455 Khz all over. If you can't find it at the bottom end
start at mid point, or wherever you can receive some sort of signal and
tune down until it stops. What is the result of this? Since the
oscillator works at higher bands its not likely to be a short from dirt
or a bend in the plates but that is sill worth looking for. Make sure
you are not measuring the frequency wrong somehow. The problem is
impossible meaning something is being missed.
Poke at it some more and post back. I am fascinated by this and
don't mind at all trying to help. Lets save this antique, probably a
pretty good receiver when working and I suspect the problem is some sort
of illusion, look at it from a different angle and it may show up. DO
NOT GIVE UP.


On 2/7/2025 1:01 PM, Emanuele Girlando via groups.io wrote:
Guys,
I performed a complete RF alignment once again.
I used a sig-gen and the SA just as a "receiver" to "see" the LO signal
and followed the service manual instructions.
LO was fine in all bands with LO signal higher than the signal by the IF
value (452KHz in my case) in all bands but the n. 4 where it was below.
The dials track the sig-gen signal with very low error in all bands.
The ANT and MIX trimcaps of bands 1&2 didn't peak, exactly as before. I
had to leave them fully released (lower C) to get the MAX output possible.
During alignment the BS dial knob was fully CW and , I confirm once
again, the BS cap had the plates all out (minimum capacity).
The radio performs well in all bands but the lower part of band 1
(<1MHz, as before).
I decided to leave it alone, I give up.
Thank you very much for your precious support, guys.
Ciao.
Emanuele (IU1KNR).
<>

--
Richard Knoppow
Los Angeles
WB6KBL
SKCC 19998
Re: S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!

 

Guys,
I performed a complete RF alignment once again.
I used a sig-gen and the SA just as a "receiver" to "see" the LO signal and followed the service manual instructions.
LO was fine in all bands with LO signal higher than the signal by the IF value (452KHz in my case) in all bands but the n. 4 where it was below.
The dials track the sig-gen signal with very low error in all bands.
The ANT and MIX trimcaps of bands 1&2 didn't peak, exactly as before. I had to leave them fully released (lower C) to get the MAX output possible.
During alignment the BS dial knob was fully CW and , I confirm once again, the BS cap had the plates all out (minimum capacity).
The radio performs well in all bands but the lower part of band 1 (<1MHz, as before).
?
I decided to leave it alone, I give up.
?
Thank you very much for your precious support, guys.
Ciao.
Emanuele (IU1KNR).
?
?
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