FS: Hallicrafters HA-8 Splatter Guard with Manual
Hallicrafters HA-8 Splatter Guard with Manual - $100 plus shipping
No way to test with a radio. Eye tube is bright. Missing the detector unit but their is a schematic of it
in the manual. It's 3 caps and 2 diodes. Looks relatively easy to build.
Includes a photocopy of the manual.
Dave N7RK
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Re: Parting out an SX-100
As Don recommended, just measure it.?
Looking at the parts list for the SX96, SX99 and SX100, it does appear the part numbers are different.
But Hallicrafters was very cost effective in building these radios and used the same cabinet many times.
I doubt they used different versions of S meters.?
May be wrong....but definitely going to put the shop rule on mine this evening
Keith
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Re: Parting out an SX-100
Hello guys, why not measure the width/height of the visible part first and compare ? …诲2
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From: [email protected] [mailto:[email protected]] On Behalf Of Donald J
Sent: Thursday, June 13, 2024 1:51 PM
To: [email protected]
Subject: Re: [HallicraftersRadios] Parting out an SX-100? The only way to tell if they are different in size is to remove and measure.? To my eye though, they look different in size.? ? Still looking for the clear bands/freqs dial covers on my SX-99.?
Are they the same as the SX-100?
-- don??? va3drl
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Noise Blanker circuit found
Here is a link to the manual for a Noise Blanker for the KWM-2.? See:
Two pentodes, two dual section triodes and eight Germanium diodes plus associated components.? Monitors the noise at 40mc and gates the IF signal in the KWM-2.? Not a simple solution but perhaps quite effective. Regards, Jim Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy
I've looked and have not found a radio that uses a noise blanker.? All I have seen is clippers which remove noise spikes above a set level.? The guitar guys mention it but it is a squelch gate which is open below a set value and closes above this set level.? So audio is muted for very low passages; one assumes to remove background hiss. Regards, JIm
Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy
Thanks jim, but first, is/has this topic swung to dealing with ignition noise only?? For an SX-117 ??? . interesting discussiuons, but what is the scope of it? Help..I’M lost??? …. again. don ?
From: [email protected] [mailto:[email protected]] On Behalf Of Jim Whartenby via groups.io
Sent: Monday, June 10, 2024 3:58 PM
To: [email protected]
Subject: Re: [HallicraftersRadios] SX-117 noise limiter behavior ? Read the enclosed excerpt from TM 11-310.? The first page shows the noise antenna circuit and lists all design changes to the series of receivers.? I would think that the noise antenna would be short so as to only pick up ignition noise.? Anything longer would subtract form the signal of interest. Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy On Monday, June 10, 2024 at 01:55:22 PM CDT, don Root <drootofallevil@...> wrote: Maynard, your theory sounds mostly good, but we need some details on what is called an antenna; will it work with my 10 feet of haywire antenna? ? ? The operation of a noise antenna and associated circuitry are
independent of the nature of the noise, whether or not it's periodic and
whether or not it's random.
Ideally, the signal antenna would receive the signal plus the offending
noise and the noise antenna would receive just the noise. The combining
network would be adjusted to combine the two signals so that their time
domain noise components would be equal in amplitude but opposite in
polarity so that they would cancel and leave only the desired signal at
the input to the receiver.
There are several potential difficulties that make this system less than
perfect in most, if not all, implementations, but it may reduce the
noise enough to be useful in some situations.
73,
Maynard
W6PAP
--
don??? va3drl
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Re: Parting out an SX-100
Hi Bruce The only way to tell if they are different in size is to remove and measure.? To my eye though, they look different in size.? Kr? D
Still looking for the clear bands/freqs dial covers on my SX-99.?
Are they the same as the SX-100?
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Re: SX-117 Noise Limiter fix
I think I suggested this possibility since the limiter was capable
of shorting out the IF signal. Congratulations on finding the culprit.
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On 6/12/2024 5:18 PM, Floyd - K8AC wrote: This started in another thread, which went off on a tangent and never
answered my question.? On my SX-117, switching the Noise Limiter on
resulted in the signals and background noise level just about
disappearing.? I wondered what should be heard when the NL is switched
on.? In my case, the problem was traced to one bad diode in the simple
noise limiter circuit.? The diode wasn't shorted or open, but exhibited
a resistance of 64 ohms in both directions.? That was enough to short
the IF signal to ground.? With the diodes replaced, when you switch the
NL on with no noise present, there is no difference in what you hear and
strong nearby signals do not cause any distortion.? The original diodes
are obsolete, but you can find them on eBay if you're willing to pay the
price.? Or, you can use 1N459A diodes as suggested by K9AXN.? They're
available from the usual suppliers.? At this time, there is no local
noise here so can't evaluate how well the NL circuit functions.
73, Floyd - K8AC
--
Richard Knoppow
Los Angeles
WB6KBL
SKCC 19998
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Re: SX-117 Noise Limiter fix
Hello, Floyd,
Yes, watched the thread wander and there was some good theory put forth but not any direct answers. Don't expect anything spectacular from the early back to back diode noise limiters of yesteryear. They can chop noise peaks but are no match for the modern dsp processing available today. Do have an R4C with the noise blanker strip and it is a definite step up. The one in my Signal One CX-7A is also pretty effective but I usually resort to my W9GR outboard DSP to really knock out noise.
Glad you id'd the defective diode, which would have been my first thought. There was a suggested improvement for the CX-7 using a pair of diodes right at the antenna input. Tried it but later removed them and went with my W9GR DSP unit.
Happy hunting and see you in the pileups!
73 ... Ed, WA9GQK
On Wednesday, June 12, 2024 at 07:18:48 PM CDT, Floyd - K8AC <floydsense@...> wrote:
This started in another thread, which went off on a tangent and never answered my question.? On my SX-117, switching the Noise Limiter on resulted in the signals and background noise level just about disappearing.? I wondered what should be heard when the NL is switched on.? In my case, the problem was traced to one bad diode in the simple noise limiter circuit.? The diode wasn't shorted or open, but exhibited a resistance of 64 ohms in both directions.? That was enough to short the IF signal to ground.? With the diodes replaced, when you switch the NL on with no noise present, there is no difference in what you hear and strong nearby signals do not cause any distortion.? The original diodes are obsolete, but you can find them on eBay if you're willing to pay the price.? Or, you can use 1N459A diodes as suggested by K9AXN.? They're available from the usual suppliers.? At this time, there is no local noise here so can't evaluate how well the NL circuit functions.??
73, Floyd - K8AC
|
This started in another thread, which went off on a tangent and never answered my question.? On my SX-117, switching the Noise Limiter on resulted in the signals and background noise level just about disappearing.? I wondered what should be heard when the NL is switched on.? In my case, the problem was traced to one bad diode in the simple noise limiter circuit.? The diode wasn't shorted or open, but exhibited a resistance of 64 ohms in both directions.? That was enough to short the IF signal to ground.? With the diodes replaced, when you switch the NL on with no noise present, there is no difference in what you hear and strong nearby signals do not cause any distortion.? The original diodes are obsolete, but you can find them on eBay if you're willing to pay the price.? Or, you can use 1N459A diodes as suggested by K9AXN.? They're available from the usual suppliers.? At this time, there is no local noise here so can't evaluate how well the NL circuit functions.??
73, Floyd - K8AC
|
A while back I was searching for? a crystal for my SX-117 to cover the first 500 Kc of 10 meters (crystal freq of 34.5 MHz).? A crystal provided by AF4K was too far off frequency and I couldn't find any other source of crystals in HC6 holders.? I ended up buying a crystal in an HC-49 holder from Krystaly in the Czech Republic.? Their price is $40 and that includes postage from Europe.? Delivery time was about 3 weeks and their communications was excellent, including lab test reports of the crystal.? The frequency was spot on.? A HC-49 crystal fits inside an HC-6 housing and you just wind the wire leads around the HC-6 pins and solder.? The HC-6 housing fits over the new crystal and can be resoldered to look like the original HC-6 crystal.? You can contact the Czech company at: krystaly@...? . 73, Floyd - K8AC
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Re: Parting out an SX-100
Still looking for the clear bands/freqs dial covers on my SX-99.?
Are they the same as the SX-100?
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Re: Parting out an SX-100
Gotcha. Thanks? Bob W4JFA?
The “un-yellowing” procedure is for the clear plastic meter cover, not the meter face itself.? I have no idea how the “un-yellowing” procedure would work on the meter face card.
Mike/
K5MGR
_____________________________ ? Mike Langner
NW
Albuquerque, NM 87114-1901
(505) 898-3212 home/home office
(505) 238-8810 cell
mlangner@...
? ? So the print stays intact? If you mentioned that, I missed it. ? On Wed, Jun 12, 2024, 12:26 AM Rudy Littrell via <kc5yl.radio=[email protected]> wrote: Donald and Mike.? ?Thanks for your de-yellow info.? Mine must have seen a lot of sun exposure. It's as yellow as a turn signal lense.? ? Gosh, Thank you for that Mike as I had not the heart to tell Rudy that I've never had or seen an SX-100 S meter cover that wasn't yellowed! And now I will be able to clear the covers on the two that I have that are quite yellowed. I'm recent to this group so missed and didn't know to look for something about meter covers. ? Note to Rudy, kc5yl --
Hello Rudy!
I failed to keep your email address, so my apologies for sending this to the group.
If your SX-100 meter lens is yellowed but otherwise in good shape, please take a look at “Retro-Brite,” a spray that restores yellowed plastic.? It’s available from many sources, including Amazon.?
Recently there was a flurry of exchanges about ways to de-yellow plastic, most of which revolved around hydrogen peroxide and sunlight, with some augmentation chemicals added in for good measure.
You should be able to restore the “yellow-free” nature of the plastic with little effort!
Good luck a& 73!
Mike/
K5MGR
_____________________________________________ ? Mike Langner
NW
Albuquerque, NM 87114-1901
(505) 898-3212 home/home office
(505) 238-8810 cell
mlangner@... ?
|
Re: Parting out an SX-100
The “un-yellowing” procedure is for the clear plastic meter cover, not the meter face itself.? I have no idea how the “un-yellowing” procedure would work on the meter face card.
Mike/
K5MGR
_____________________________ ? Mike Langner
929 Alameda Road NW
Albuquerque, NM 87114-1901
(505) 898-3212 home/home office
(505) 238-8810 cell
mlangner@...
?
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From: [email protected] <[email protected]> On Behalf Of Bob
Sent: Wednesday, June 12, 2024 2:20 PM
To: [email protected]
Subject: Re: [HallicraftersRadios] Parting out an SX-100? So the print stays intact? If you mentioned that, I missed it. ? On Wed, Jun 12, 2024, 12:26 AM Rudy Littrell via <kc5yl.radio=[email protected]> wrote: Donald and Mike.? ?Thanks for your de-yellow info.? Mine must have seen a lot of sun exposure. It's as yellow as a turn signal lense.? ? Gosh, Thank you for that Mike as I had not the heart to tell Rudy that I've never had or seen an SX-100 S meter cover that wasn't yellowed! And now I will be able to clear the covers on the two that I have that are quite yellowed. I'm recent to this group so missed and didn't know to look for something about meter covers. ? Note to Rudy, kc5yl --
Hello Rudy!
I failed to keep your email address, so my apologies for sending this to the group.
If your SX-100 meter lens is yellowed but otherwise in good shape, please take a look at “Retro-Brite,” a spray that restores yellowed plastic.? It’s available from many sources, including Amazon.?
Recently there was a flurry of exchanges about ways to de-yellow plastic, most of which revolved around hydrogen peroxide and sunlight, with some augmentation chemicals added in for good measure.
You should be able to restore the “yellow-free” nature of the plastic with little effort!
Good luck a& 73!
Mike/
K5MGR
_____________________________________________ ? Mike Langner
NW
Albuquerque, NM 87114-1901
(505) 898-3212 home/home office
(505) 238-8810 cell
mlangner@... ?
|
Re: Parting out an SX-100
So the print stays intact? If you mentioned that, I missed it. Bob W4JFA
On Wed, Jun 12, 2024, 12:26 AM Rudy Littrell via <kc5yl.radio= [email protected]> wrote: Donald and Mike.? ?Thanks for your de-yellow info.? Mine must have seen a lot of sun exposure. It's as yellow as a turn signal lense.?
Over, Rudy?
kc5yl??
Gosh, Thank you for that Mike as I had not the heart to tell Rudy that I've never had or seen an SX-100 S meter cover that wasn't yellowed!
And now I will be able to clear the covers on the two that I have that are quite yellowed.
I'm recent to this group so missed and didn't know to look for something about meter covers.
Best d
Note to Rudy, kc5yl --
Hello Rudy!
I failed to keep your email address, so my apologies for sending this to the group.
If your SX-100 meter lens is yellowed but otherwise in good shape, please take a look at “Retro-Brite,” a spray that restores yellowed plastic.? It’s available from many sources, including Amazon.?
Recently there was a flurry of exchanges about ways to de-yellow plastic, most of which revolved around hydrogen peroxide and sunlight, with some augmentation chemicals added in for good measure.
You should be able to restore the “yellow-free” nature of the plastic with little effort!
Good luck a& 73!
Mike/
K5MGR
_____________________________________________ ? Mike Langner
NW
Albuquerque, NM 87114-1901
(505) 898-3212 home/home office
(505) 238-8810 cell
mlangner@...
?
|
Re: Parting out an SX-100
Donald and Mike.? ?Thanks for your de-yellow info.? Mine must have seen a lot of sun exposure. It's as yellow as a turn signal lense.?
Over, Rudy?
kc5yl??
Gosh, Thank you for that Mike as I had not the heart to tell Rudy that I've never had or seen an SX-100 S meter cover that wasn't yellowed!
And now I will be able to clear the covers on the two that I have that are quite yellowed.
I'm recent to this group so missed and didn't know to look for something about meter covers.
Best d
Note to Rudy, kc5yl --
Hello Rudy!
I failed to keep your email address, so my apologies for sending this to the group.
If your SX-100 meter lens is yellowed but otherwise in good shape, please take a look at “Retro-Brite,” a spray that restores yellowed plastic.? It’s available from many sources, including Amazon.?
Recently there was a flurry of exchanges about ways to de-yellow plastic, most of which revolved around hydrogen peroxide and sunlight, with some augmentation chemicals added in for good measure.
You should be able to restore the “yellow-free” nature of the plastic with little effort!
Good luck a& 73!
Mike/
K5MGR
_____________________________________________ ? Mike Langner
929 Alameda Road NW
Albuquerque, NM 87114-1901
(505) 898-3212 home/home office
(505) 238-8810 cell
mlangner@...
?
|
Re: Parting out an SX-100
Gosh, Thank you for that Mike as I had not the heart to tell Rudy that I've never had or seen an SX-100 S meter cover that wasn't yellowed!
And now I will be able to clear the covers on the two that I have that are quite yellowed.
I'm recent to this group so missed and didn't know to look for something about meter covers.
Best d
Note to Rudy, kc5yl --
Hello Rudy!
I failed to keep your email address, so my apologies for sending this to the group.
If your SX-100 meter lens is yellowed but otherwise in good shape, please take a look at “Retro-Brite,” a spray that restores yellowed plastic.? It’s available from many sources, including Amazon.?
Recently there was a flurry of exchanges about ways to de-yellow plastic, most of which revolved around hydrogen peroxide and sunlight, with some augmentation chemicals added in for good measure.
You should be able to restore the “yellow-free” nature of the plastic with little effort!
Good luck a& 73!
Mike/
K5MGR
_____________________________________________ ? Mike Langner
929 Alameda Road NW
Albuquerque, NM 87114-1901
(505) 898-3212 home/home office
(505) 238-8810 cell
mlangner@...
?
|
Re: Parting out an SX-100
Note to Rudy, kc5yl --
Hello Rudy!
I failed to keep your email address, so my apologies for sending this to the group.
If your SX-100 meter lens is yellowed but otherwise in good shape, please take a look at “Retro-Brite,” a spray that restores yellowed plastic.? It’s available from many sources, including Amazon.?
Recently there was a flurry of exchanges about ways to de-yellow plastic, most of which revolved around hydrogen peroxide and sunlight, with some augmentation chemicals added in for good measure.
You should be able to restore the “yellow-free” nature of the plastic with little effort!
Good luck a& 73!
Mike/
K5MGR
_____________________________________________ ? Mike Langner
929 Alameda Road NW
Albuquerque, NM 87114-1901
(505) 898-3212 home/home office
(505) 238-8810 cell
mlangner@...
?
|
Re: Parting out an SX-100
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On Tue, Jun 11, 2024 at 11:48?AM Rudy Littrell via <kc5yl.radio= [email protected]> wrote: Donald,? ?I need a clear unyellowed meter lense for a SX-100. Do you have one??
Over, Rudy Littrell?
kc5yl??
Let me know what you want and a small amount for it/them along with a reasonable shipping cost ...
If you have a picture of the specific item(s) - that helps nail it for me.
Best
Donald
|
Re: Parting out an SX-100
Donald,? ?I need a clear unyellowed meter lense for a SX-100. Do you have one??
Over, Rudy Littrell?
kc5yl??
Let me know what you want and a small amount for it/them along with a reasonable shipping cost ...
If you have a picture of the specific item(s) - that helps nail it for me.
Best
Donald
|
Re: SX-117 noise limiter behavior
The ANC-4 by Timewave is a very effective device for limiting local noise. ?I get more than 40dB reduction, sometimes more, so that weak signals stand out against an almost silent background. ?MFJ makes a similar device. ?These devices use an active RF circuit to amplify the offending noise from a separate antenna, and then beat it against the same noise in your main antenna. ?They really work. I see some used ones online around 125 bucks. ?
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On Jun 10, 2024, at 1:52 PM, Maynard Wright, P. E., W6PAP via < ma.wright@...> wrote:
The use of a noise antenna and associated circuitry is independent of the nature of the noise, whether or not it's periodic and whether or not it's random. Ideally, the signal antenna would receive the signal plus the offending noise and the noise antenna would receive just the noise. The combining network would be adjusted to combine the two signals so that their time domain noise components would be equal in amplitude but opposite in polarity so that they would cancel and leave only the desired signal at the input to the receiver. There are several potential difficulties that make this system less than perfect in most, if not all, implementations, but it may reduce the noise enough to be useful in some situations. 73, Maynard W6PAP On 6/9/24 17:11, Mike Feher wrote: It seems to me, that since noise is neither correlate-able or
stochastic, elimination is not possible. Also the multiple antenna
theory is out the window since RF generated noise travels at the speed
of light. 73 – Mike
Mike B. Feher, N4FS
89 Arnold Blvd.
Howell NJ 07731
908-902-3831
*From:* [email protected] <[email protected]>
*On Behalf Of *Maynard Wright, P. E., W6PAP via
*Sent:* Sunday, June 9, 2024 7:31 PM
*To:* [email protected]
*Subject:* Re: [HallicraftersRadios] SX-117 noise limiter behavior
Another technique for reducing or eliminating noise was to introduce
local noise to the front end of a receiver from a local "noise antenna."
The amplitude and phase of that noise could be adjusted to, hopefully,
cancel the noise received by the signal antenna.
Early BC-342 and BC-312 receivers featured a noise suppression circuit
of this type. War Department TM 11-850 states that the noise antenna
was intended to eliminate ignition noise when the receiver was mounted
in a vehicle.
By the time my BC-342-N was born (1942), the noise antenna and
associated circuitry were omitted, so that circuit may not have worked
well. The September, 1946 revision of the TM notes that spare parts
were no longer available for the noise suppression circuit and
recommends removing it if any of the components fail.
MFJ has featured at least one similar unit, the MFJ-1026, which is now
listed as sold out. There are other such units available but I have no
experience with them.
73,
Maynard
W6PAP
|
Re: SX-117 noise limiter behavior
The use of a noise antenna and associated circuitry is independent of
the nature of the noise, whether or not it's periodic and whether or not
it's random.
Ideally, the signal antenna would receive the signal plus the offending
noise and the noise antenna would receive just the noise. The combining
network would be adjusted to combine the two signals so that their time
domain noise components would be equal in amplitude but opposite in
polarity so that they would cancel and leave only the desired signal at
the input to the receiver.
There are several potential difficulties that make this system less than
perfect in most, if not all, implementations, but it may reduce the
noise enough to be useful in some situations.
73,
Maynard
W6PAP
toggle quoted message
Show quoted text
On 6/9/24 17:11, Mike Feher wrote: It seems to me, that since noise is neither correlate-able or
stochastic, elimination is not possible. Also the multiple antenna
theory is out the window since RF generated noise travels at the speed
of light. 73 – Mike
Mike B. Feher, N4FS
89 Arnold Blvd.
Howell NJ 07731
908-902-3831
*From:* [email protected] <[email protected]>
*On Behalf Of *Maynard Wright, P. E., W6PAP via groups.io
*Sent:* Sunday, June 9, 2024 7:31 PM
*To:* [email protected]
*Subject:* Re: [HallicraftersRadios] SX-117 noise limiter behavior
Another technique for reducing or eliminating noise was to introduce
local noise to the front end of a receiver from a local "noise antenna."
The amplitude and phase of that noise could be adjusted to, hopefully,
cancel the noise received by the signal antenna.
Early BC-342 and BC-312 receivers featured a noise suppression circuit
of this type. War Department TM 11-850 states that the noise antenna
was intended to eliminate ignition noise when the receiver was mounted
in a vehicle.
By the time my BC-342-N was born (1942), the noise antenna and
associated circuitry were omitted, so that circuit may not have worked
well. The September, 1946 revision of the TM notes that spare parts
were no longer available for the noise suppression circuit and
recommends removing it if any of the components fail.
MFJ has featured at least one similar unit, the MFJ-1026, which is now
listed as sold out. There are other such units available but I have no
experience with them.
73,
Maynard
W6PAP
|
don Root
Jim Whartenby
Donald J
Floyd - K8AC
Bruce Collins
Bob
Mike Langner