The following files have been uploaded to
the Files area of the [email protected] group.
By: lobos305@...
Description:
E8935 Assembly Level Repair Manual
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Re: 8935 Service Manual & Power Supply Rebuild
Hi Patrick
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You might find this article interesting ?by Agilent / HP 8935? E6380A????????Amtronix Instruments, Inc
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Also did find a service manual Part number E6380-90015 as apparently there is a family of them 8935 / E6380 / 6381 / 6382
But it was on a site that wanted to update me to windows ?10
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Regards Paul
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Additionally, I spent the morning looking for the repair manual for this unit but came up blank. If anyone knows where I can find that, I'd greatly appreciate it. Trying to figure out "the right way" to take the thing apart as opposed to just blindly removing screws.
Thanks all!
Patrick
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8935 Service Manual & Power Supply Rebuild
Hi all! Happy to have found this group.
I've owned my 8935 for about two years now and it's been great for my radio needs. However recently it's started throwing the AFCI breaker for my lab. I've temporarily worked around this by plugging it in via extension cord to a regular GFCI outlet, but I'd like to get it back up and running. I've heard capacitors in the PSU can be problematic, so I'd love to get info on what's required to replace those.
Additionally, I spent the morning looking for the repair manual for this unit but came up blank. If anyone knows where I can find that, I'd greatly appreciate it. Trying to figure out "the right way" to take the thing apart as opposed to just blindly removing screws.
Thanks all!
Patrick
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Re: 8924c 60/100 watt upgrade kit
Yes - that was the kit I had used where you sent back the card, etc.? ?Ok well again I was just curious.? And yes, a screw gun would help big time with this work.
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Thanks so much for all of the info - Sig - KB2HHU...
On Friday, October 29, 2021, 03:10:53 PM EDT, Ralph Mowery wrote:
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It was over 10 years ago I bought the upgrade 60 watt? kit from ebay .? It had the attenuator, an emblem to paste over the BNC and a card to up load the info.? I had to send the card back for a $ 50 or so deposit.? I do not see that kit any more.
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Re: 8924c 60/100 watt upgrade kit
This was in the files.? All or almost all of the Yahoogroup files are here.? It's just a matter of finding them.? Ralph helped once again by giving me the file title. ?HP-8924C_100W_upgrade.pdfHank
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Re: 8924c 60/100 watt upgrade kit
It was over 10 years ago I bought the upgrade 60 watt? kit from ebay .? It had the attenuator, an emblem to paste over the BNC and a card to up load the info.? I had to send the card back for a $ 50 or so deposit.? I do not see that kit any more.
I later bought a 20 db pad to put in another.? Someone had uploaded the files for a 20 db pad so I loaded that into the 2nd 8924c and all was well.
The card changes some date somewhere in the 8924c, but I don't know where.? It is not the place in one of the setup screens where you can plug in your own offset.
If you think there is only a zillion screws , you should be careful and not do what I did and drop one of the screws down into the module with the display tube.? That is another zillion. I used a battery drill and torx bit to remove most of the screws.
Ralph ku4pt
On Friday, October 29, 2021, 01:59:43 PM EDT, Siegmund Souza via groups.io <zigs68@...> wrote:
Yes - I saw those pads on eBay and that was what I did with the one 8924c that was upgraded.? You got a pad where you removed the one that was there and soldered in the new one which had the higher attenuation and the heatsink was the same meaning you used the one you had.? There was a PCMCIA calibration card that came with it where you uploaded some data.? Unfortunately I do not know much about what was uploaded.? I guess knowing the attenuation you could just do the same offset in the settings and that is all?? ?Maybe that is what uploading that data from the card did.
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Checking the fit would be important with this indeed.? I do not see any files that show how to replace the pad but from what I recall it was not difficult other than removing a zillion screws (exaggeration somewhat - not too much) to get to the heatsink.? I do see in the files the use of an external attenuator and how to set that up.
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I was just curious if those kits on ebay still existed somewhere.? Probably most went the route of the external attenuator which is fine since its not like you are going to worry about the 8924C being "less portable" than it is having to connect the attenuator and cables to test.? It stays on the table or bench and that is it.
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Thanks - Sig - KB2HHU? ?.
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Re: 8924c 60/100 watt upgrade kit
Yes - I saw those pads on eBay and that was what I did with the one 8924c that was upgraded.? You got a pad where you removed the one that was there and soldered in the new one which had the higher attenuation and the heatsink was the same meaning you used the one you had.? There was a PCMCIA calibration card that came with it where you uploaded some data.? Unfortunately I do not know much about what was uploaded.? I guess knowing the attenuation you could just do the same offset in the settings and that is all?? ?Maybe that is what uploading that data from the card did.
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Checking the fit would be important with this indeed.? I do not see any files that show how to replace the pad but from what I recall it was not difficult other than removing a zillion screws (exaggeration somewhat - not too much) to get to the heatsink.? I do see in the files the use of an external attenuator and how to set that up.
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I was just curious if those kits on ebay still existed somewhere.? Probably most went the route of the external attenuator which is fine since its not like you are going to worry about the 8924C being "less portable" than it is having to connect the attenuator and cables to test.? It stays on the table or bench and that is it.
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Thanks - Sig - KB2HHU? ?.
On Friday, October 29, 2021, 01:09:49 PM EDT, Ralph wrote:
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There are some on ebay for about $ 30 .? This may not be the one you need, but similar.? You have to check the physical size to see if it will fit in.
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Re: 8924c 60/100 watt upgrade kit
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You really need an almost 20 db pad as the 3 watt version already has a 4 db pad that is removed.? I think the heat sink is the same for the 60 watt and the 3 watt versions, so all you need is the insert.? I have a file that shows how to do that if you do not see it in the file section here.
There are some on ebay for about $ 30 .? This may not be the one you need, but similar.? You have to check the physical size to see if it will fit in.
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On Friday, October 29, 2021, 01:01:48 PM EDT, Siegmund Souza via groups.io <zigs68@...> wrote:
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Thanks Ralph - that is an option and there were other posts that mention where to go to create the offset in the power.? You would need a 16 dB attenuator ideally to put the 100 watts down to 3 watts from what I calculated.? Attenuators for a 100 watt rating seem expensive though but maybe I am looking in the wrong places.
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Thanks again - Sig - KB2HHU
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Re: 8924c 60/100 watt upgrade kit
Thanks Ralph - that is an option and there were other posts that mention where to go to create the offset in the power.? You would need a 16 dB attenuator ideally to put the 100 watts down to 3 watts from what I calculated.? Atenuators for a 100 watt rating seem expensive though but maybe I am looking in the wrong places.
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Thanks again - Sig - KB2HHU
On Friday, October 29, 2021, 12:56:09 PM EDT, Ralph Mowery via groups.io <ku4pt@...> wrote:
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You may want to do like I did a few years back.? Just buy an attenuator from ebay of a 100 watt rating that will fit the heatsink that is already in the 8924C.? There were some files in the files section to download what you need to make it work or you can just use the offset built into one of the setup screens.
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Ralph ku4pt.
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Re: 8924c 60/100 watt upgrade kit
You may want to do like I did a few years back.? Just buy an attenuator from ebay of a 100 watt rating that will fit the heatsink that is already in the 8924C.? There were some files in the files section to download what you need to make it work or you can just use the offset built into one of the setup screens.
Ralph ku4pt.
On Friday, October 29, 2021, 12:44:49 PM EDT, Siegmund Souza via groups.io <zigs68@...> wrote:
Just asking about availability of the 8924c upgrade kit.? I did install this kit to an 8924c a long time ago where the higher dB value attenuator "pad" inside\soldered to the heatsink was changed and I had a calibration card with instructions were I set up the 8924c to show the correct power values, etc.? Is Amtronix the only place that has these kits these days which I guess sells you the whole heatsink assembly with the correct attenuation?? There used to be listings on eBay but of course these units are very old and not as available as they were way back when.?
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8924c 60/100 watt upgrade kit
Just asking about availability of the 8924c upgrade kit.? I did install this kit to an 8924c a long time ago where the higher dB value attenuator "pad" inside\soldered to the heatsink was changed and I had a calibration card with instructions were I set up the 8924c to show the correct power values, etc.? Is Amtronix the only place that has these kits these days which I guess sells you the whole heatsink assembly with the correct attenuation?? There used to be listings on eBay but of course these units are very old and not as available as they were way back when.?
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Interesting board extenders
Just something I thought I would share, not mine by any means....
Wally KC9INK
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Re: Much too much power in to E8285A RF IN/OUT connector
There IS Hope;
There is an internal overload cutoff, with luck it tripped.?
1. [shift] Meas Reset or
"Green-Button PRESET" reset should clear it...
Find something known up 100mW to 2W? make sure it tracks through range...
my 8935 eats 75W...
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Re: Much too much power in to E8285A RF IN/OUT connector
You could try to generate an output to see if that is still there.
There is an ¡°overload allowance¡± (power & time) as I recall, before destruction.
I have 6 dB pads on my inputs because I am a klutz, myself.
Larry
AC9OX
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Much too much power in to E8285A RF IN/OUT connector
Well...it had to happen someday.
I was trying to find all the problems in a ft767GX from a friend. It was a "tech special" parts radio, and "had no transistors on PA". I touched the MOX button with the arm and the E8285A alarm told me something was wrong...yes, the radio had the transistors on the PA, and I sent 120 watts to the RF In/Out connector.
Any tips on where do I begin diagnosing? I know there are no schematics of the E8285A available, so any direction on how to begin will be of great help.
Thanks.
Alexandre, PU2SEX
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Re: DC Blocker - why not?
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From: [email protected] <[email protected]>
On Behalf Of Alexandre Souza via groups.io
Sent: 18 September 2021 08:40
To: [email protected]
Subject: Re: [HP8920/8935 Family] DC Blocker - why not?
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So bad their?carborundum?resistors are unobtainium or too expensive to be fixed. :(? ? ? ?guess how do I know. :(
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The Bird 100W block attenuators come apart ok. Quite chunky though ¨C not for hanging off a front panel!
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Re: DC Blocker - why not?
So bad their?carborundum?resistors are unobtainium or too expensive to be fixed. :(? ? ? ?guess how do I know. :(
The Bird 100W block attenuators come apart ok. Quite chunky though ¨C not for hanging off a front panel!
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Re: DC Blocker - why not?
Last time i repurposed one was a 75 ohm BNC type.? I rebuilt as a 50 ohm 60 db for close-in T- hunting.
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Re: DC Blocker - why not?
Some of the BNCs will unscrew and you might have to replace the insides, so if you smoke one dont throw it away.
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Re: DC Blocker - why not?
The Bird 100W block attenuators come apart ok. Quite chunky though ¨C not for hanging off a front panel!
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Colin
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From: [email protected] <[email protected]>
On Behalf Of Hank Riley via groups.io
Sent: 17 September 2021 17:54
To: [email protected]
Subject: Re: [HP8920/8935 Family] DC Blocker - why not?
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jb or anyone,
Have you ever seen a commercial attenuator that you could take apart (in the proper way without sawing or grinding)?
So far I haven't.
Hank
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On Fri, Sep 17, 2021 at 12:29 PM, jb wrote:
I like the idea of cheap protection Instead of expensive and labor intensive repairs.
I like the idea of a 3 to 10db attenuator that you can take apart and add SMD cap and fuse.?
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Patrick W3AXL
MATT SQUIRE
Alexandre Souza