Re: I need a new/used lab computer
Maybe. I don¡¯t find any PCs in ewaste at work, probably because of proprietary information on the hdds. I will ask around. Thanks. Jim
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On Mar 6, 2025, at 12:24?PM, Jim Ford via groups.io <james.ford@...> wrote:
?My garage lab computer went kaput recently, and I need to get another one to control my instruments via GPIB and USB. I had a tower running Windows 7, although it was originally my wife¡¯s computer running (ick!) Windows Vista. Sooooo slow! Anyway, I don¡¯t need anything fancy, just a PCI slot for the GPIB card, Ethernet jack for Internet connection, and at least 4 USB jacks (kbd, mouse, USB microscope, GPSDO). Mini tower or thin client would be great. Anybody have a PC they don¡¯t need? Thanks in advance.
Jim Ford
Laguna Hills, California, USA
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Re: [HP-Agilent-Keysight-equipment] I need a new/used lab computer
Jim-
let me check as I have a tower doing nothing...hss not been used for long time, will know when I get to the shop over the weekend.
shop is? in no. SF bay area
¸é±ð²Ô¨¦±ð
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On 3/6/25 12:24 PM, Jim Ford via groups.io wrote: My garage lab computer went kaput recently, and I need to get another one to control my instruments via GPIB and USB. I had a tower running Windows 7, although it was originally my wife¡¯s computer running (ick!) Windows Vista. Sooooo slow! Anyway, I don¡¯t need anything fancy, just a PCI slot for the GPIB card, Ethernet jack for Internet connection, and at least 4 USB jacks (kbd, mouse, USB microscope, GPSDO). Mini tower or thin client would be great. Anybody have a PC they don¡¯t need? Thanks in advance.
Jim Ford
Laguna Hills, California, USA
.
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Re: [HP-Agilent-Keysight-equipment] I need a new/used lab computer
Jim,
Do you have anyone in your environment with a not too old laptop? Get it for a box of cigars, install an SSD and Linux Mint. You're back in business!
Best 73 de Harke
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On 6-3-2025 21:24, Jim Ford via groups.io wrote: My garage lab computer went kaput recently, and I need to get another one to control my instruments via GPIB and USB. I had a tower running Windows 7, although it was originally my wife¡¯s computer running (ick!) Windows Vista. Sooooo slow! Anyway, I don¡¯t need anything fancy, just a PCI slot for the GPIB card, Ethernet jack for Internet connection, and at least 4 USB jacks (kbd, mouse, USB microscope, GPSDO). Mini tower or thin client would be great. Anybody have a PC they don¡¯t need? Thanks in advance.
Jim Ford
Laguna Hills, California, USA
|
I need a new/used lab computer
My garage lab computer went kaput recently, and I need to get another one to control my instruments via GPIB and USB. I had a tower running Windows 7, although it was originally my wife¡¯s computer running (ick!) Windows Vista. Sooooo slow! Anyway, I don¡¯t need anything fancy, just a PCI slot for the GPIB card, Ethernet jack for Internet connection, and at least 4 USB jacks (kbd, mouse, USB microscope, GPSDO). Mini tower or thin client would be great. Anybody have a PC they don¡¯t need? Thanks in advance.
Jim Ford
Laguna Hills, California, USA
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Re: 2465A start-up problem
Hi
NO NO NO Standard 1W resistors only have a working voltage of 350V and some of rare ones of 500V, use resistors from the Vishay VR range or equivalent. R4434 must be suspected.
G Edmonds On Thursday 6 March 2025 at 16:34:03 GMT, Mark Vincent via groups.io <orangeglowaudio@...> wrote:
James,
The focus problem may be due to resistors in and around the focus circuit. They should be raised to 1W types due to the voltage drop across them. These resistors are from B+ to the collectors and from C to B of a few transistors on the h-v board. The part numbers are from Mouser. The 150,000 ohm: 71-CCF60-150K-E3, 180,000 ohm: 279-H4P180KFDA, 332,000 ohm: 71-CCF60-332K-E3, 442,000 ohm: 71-CMF60442K00FEWF (12 week delay) or (2) 660-MF1/2CC2213F (in series), 430,000 ohm: 279-H4P430KFZA, 100meg: 708-HVA12FA100M or (measure in mm the hole spacing of the original carbon then select the on that will drop in which will be larger in wattage than original). If yours has the two 39meg 1/4w carbons on the bottom board, use two 594-MBE04140C2005FC1 in series. These will be R710 and R910.
When you finish recapping the unit, use high temp, low ESR and long life types. Make sure to get the polarity and look to see if yours has the incorrect voltage and values of two condensers in the supply. Replace them as you find them. There are resistors in the supply that should be increased in wattage. The two 4,7mfd tantalums likely will test bad. I used 50V film types to replace them. M. Yachad has a kit for these to recap and some resistors that should be replaced.
Mark
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Re: 2465A start-up problem
James,
The focus problem may be due to resistors in and around the focus circuit. They should be raised to 1W types due to the voltage drop across them. These resistors are from B+ to the collectors and from C to B of a few transistors on the h-v board. The part numbers are from Mouser. The 150,000 ohm: 71-CCF60-150K-E3, 180,000 ohm: 279-H4P180KFDA, 332,000 ohm: 71-CCF60-332K-E3, 442,000 ohm: 71-CMF60442K00FEWF (12 week delay) or (2) 660-MF1/2CC2213F (in series), 430,000 ohm: 279-H4P430KFZA, 100meg: 708-HVA12FA100M or (measure in mm the hole spacing of the original carbon then select the on that will drop in which will be larger in wattage than original). If yours has the two 39meg 1/4w carbons on the bottom board, use two 594-MBE04140C2005FC1 in series. These will be R710 and R910.
When you finish recapping the unit, use high temp, low ESR and long life types. Make sure to get the polarity and look to see if yours has the incorrect voltage and values of two condensers in the supply. Replace them as you find them. There are resistors in the supply that should be increased in wattage. The two 4,7mfd tantalums likely will test bad. I used 50V film types to replace them. M. Yachad has a kit for these to recap and some resistors that should be replaced.
Mark
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Re: Tek 2445B and 2465B power supply recap and Dallas NVRAM replacements?
On Mon, Feb 5, 2024 at 07:48 AM, Ozan wrote:
FM18W08
I have also with success replaced DS1230 Dallas chips in HP scopes with FM18W08 and a SOIC to 28DIP board from CPC Farnel + IC socket = 5$/GBP and works well.
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Re: 2465A start-up problem
Last night I swapped the entire supply over and the problem remains. Surely the chances of two PSU's having identical and 'uncommon' faults, rules out that possibility.
Considering that we have both vertical and horizontal deflection, Sweep, and intensity control, then it seems to me that I need to deep dive into the focus section.
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2430A I had last week had no display, a 2.7Uf tant cap was loading a reg circuit (top PCB rear left)
--
Jeffeelcr
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Due to a mistake on a drawing Tektronix had 012-0482-00/01 cables made with RG-58/U cable.
They have now corrected the error and have the correct RG223/U cable and have 012-0482-01 made with the correct cable.
--
Jeffeelcr
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Re: SC503 Interesting Wave Form
On Wed, Feb 26, 2025 at 12:43 PM, Barry Breaux wrote: I changed DC502 to SC503.
Hello,
I posted a picture in photo of a waveform being drawn by an SC503. I asked if
anyone wanted to guess the cause. I know the answer, but take a guess if you
want. I will post the component failure a little later.
/g/TekScopes/album?id=300884
Barry
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Re: unresponsive 492; possible memory issue
Makes sense. They added the optocoupler later, it looks like.
It doesn't look like the 492 used the line trigger for power-good reset, at
least at first glance, so it sounds like the disconnected capacitor may have
been failing to suppress some noise that kept the controller from booting
properly.
-- john, KE5FX
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-----Original Message----- From: [email protected] < [email protected]> On Behalf Of Adam R. Maxwell via groups.io Sent: Monday, March 3, 2025 10:55 PM To: [email protected]Subject: Re: [TekScopes] unresponsive 492; possible memory issue I couldn't find an optocoupler in the power supply schematic, and RESET on the processor board schematic led me to GPIB board. Likely that's me being clueless and looking at the wrong thing, but I found an old post of yours that mentioned a 495 using the line-trigger:
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Re: SC503 Interesting Wave Form
Hi all,
I'm having an issue today with 'View/Reply online' (I'm not able to find the window to enter a message) and that's the reason for using 'Reply to group'.If Edward's 'Please explain more' request refers to my previous message 'Not clear about the role of DC502 here...' then Barry's first sentence of this topic should be re-read
RegardsT
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Re: 2465A start-up problem
The PSU hasn't been fully recapped although it the ESR was checked
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Re: 2465A start-up problem
Hi Menahem.
Before, it wouldn't turn on. The two 0.068?F's had exploded.
James.
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Re: 2465A start-up problem
And before the RIFA's were replaced, what was its condition?
Menahem
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Re: SC503 Interesting Wave Form
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Re: VintageTEK demo boards are back
On Tue, Mar 4, 2025 at 04:37 PM, Dave Brown wrote: The museum is open to the public with no admission charge. We participate in
external STEM events for free. The museum relies 100% on volunteers,
donations, and eBay sales for its operation. These sales help keep the museum
open. Hi Dave, If you feel that this discussion is harmful to the Museum's revenue stream, then I will certainly "cease and desist". I'm just a hobbyist, and I don't want my interests and curiosities to harm a small business. The museum I work at ( ) struggles with funds of course also. We do charge admission, and have several paid staff in addition to a number of volunteers like me; but we also have over 50 acres of property and 8 or 9 buildings to maintain (one of which is on the CO Historic Register). We host multiple school group tours every week, host STEaM camps, etc. We think we are one of the very best museums of its kind anywhere. Pete
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Re: 2465A start-up problem
Nothing shorted nor open on the A9 board
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Re: VintageTEK demo boards are back
Thank you Craig. The museum is open to the public with no admission charge. We participate in external STEM events for free. The museum relies 100% on volunteers, donations, and eBay sales for its operation. These sales help keep the museum open. If you haven't noticed lately, a lot of museums have folded.
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Mr Lurpak's Electronics Rescue
James55
saipan59 (Pete)