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Author Topic: HQ-140X  (Read 8167 times)
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W9BHI
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« on: February 24, 2012, 11:18:04 AM »

Anybody in Ill. that could do an alignment on a Hammarlund HQ-140X?
I replaced the paper and electrolytic caps as well as new tubes in the RF and IF stages.
It is functional on 160, 80 and 40.
The dial cal is way off on 20 and is nearly deaf on 15 and 10.
Anybody willing to tackle this?
Thanks,
Don W9BHI
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KM1H
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« Reply #1 on: February 24, 2012, 03:23:10 PM »

Finish the job by replacing all the out of spec resistors.

Its a fairly sensitive radio when completed altho the RF and mixer stages could use some simple tube swaps such as a 6BZ6 (reverse pins 2 and 7 wiring) or 6GM6 which will require a few added resistors to reduce plate voltage and eliminate oscillations but Ive used it across many brands and models and is my favorite 7 pin pentode as an RF amp.

A 6BY6 for the mixer is a direct swap.

The 6C4 should also be new to be sure oscillator injection is sufficient on the highest frequencies.

Im in NH and work on these and others regularly if you dont find someone local.

Carl
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WQ9E
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« Reply #2 on: February 24, 2012, 07:11:40 PM »

Don,

If you have AM gear you could check into the Midwest Classic Radio Net tomorrow morning on 3885 at 7:30 AM CST.  There are a number of members in the greater Chicagoland area and someone may be able to help you.

I would take Carl's advice about the resistors because there were quite a few out of spec resistors when I went through my HQ-140X several years ago.

Right now I am way too busy with my "real" job to take on any projects or I would be happy to help you out.  I am also quite a few miles south of you in the central part of the state.

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Rodger WQ9E
W9BHI
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« Reply #3 on: February 26, 2012, 01:22:41 PM »

Thanks guys for the suggestions.
I am going to check all of the resistors and see if any are out of tolerance.
I am also going to clean the band switch because it is getting intermittant when touched.
Thanks again,
Don W9BHI
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KM1H
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« Reply #4 on: February 26, 2012, 05:28:25 PM »

Just dont go flooding it with DeWrex-It otherwise you may be looking for replacement wafers.

In my 120 thru 140X's I found that 1-2 oscillator trimmers in each radio to be stability culprits (by tapping) and replaced them with Johnson sub mini air variables.

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W9BHI
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« Reply #5 on: February 27, 2012, 09:47:35 AM »

What would I use to clean the bandswitch if I shouldn't use DeOxit?
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KB2WIG
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« Reply #6 on: February 27, 2012, 11:12:08 AM »

I think its more of a what Carl said; ` don't "flood" the bandswitch ` type of thing.
(Like Mr Farad said, guilty as charged.)

I've followed sugestions such as use a tooth pick, Q-tip. pipe cleaned cotton ba's on a hemostat etc. to place the miracle fluid  selectively on a/the part.


klc
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The Slab Bacon
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« Reply #7 on: February 27, 2012, 11:33:00 AM »

I use a mixture of 1 part mineral spirits to 1 part lacquer thinner. Apply with a Q-tip or small artist's paintbrush.

The mineral spirits slows down the evaporation a tad so you have time to work the switch. Cleans off old hard grease, and many other types of mung. If you use a bug enough brush too wash the switch out, lat it set for an hour or 2 and it will completely dry out of old porus phenolic wafers and leave no traces of ever being there.

If residue is NOT an issue, and also in potentiometers, I have used WD-40 for years. Good schtuff!! but it does leave a residue.
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"No is not an answer and failure is not an option!"
KM1H
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« Reply #8 on: February 27, 2012, 05:43:50 PM »

I usually use Tarn-X diluted about 2:1 and a Q Tip to wipe the tarnish off switch wipers. Rotating the switch while wiping breaks thru the tarnish on the fixed contacts. Wipe down with Q Tips and disc brake cleaner on the Q Tip. 

Only in extreme situations do I use DeWrex-It and you dont want to get it on ceramic or phenolic were it can create a conductive path or swell and ruin the phenolic. A drop from the small bottle applicator or on a thin wire is all thats needed.
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W9BHI
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« Reply #9 on: February 27, 2012, 09:49:02 PM »

Well tonight I checked all of the resistors and the worst one was 9% out of tolerance.
I cleaned the tuning and bandspread variable caps rotor ground wipers 60 year old black waxy grease off with DeOxit and some Qtips.
I then used about 50 Qtips and some DeOxit to remove the black grunge off of the bandswitch contacts.
I used compressed air to dry off any residue.
It now tunes on ALL of it's bands.
I have a digital dial for it and I tweaked the osc. trimmers and it is now fairly accurate on the tuning dial.
Thanks for all of the suggestions.

Don W9BHI
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Carl WA1KPD
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« Reply #10 on: February 28, 2012, 07:00:37 PM »

Don,
The 140  X is one of my favorite receivers.  I think it looks cool, has a nice feel to it and performs well.

One thing to be careful of is that the dial lights are the correct ones. Some hammy hambone put the wrong ones in mine and melted a black hole in the bandspread dial. A replacement has been impossible to find.

Carl

/KPD
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Carl

"Okay, gang are you ready to play radio? Are you ready to shuffle off the mortal coil of mediocrity? I am if you are." Shepherd
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