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Electronics => Metrology => Topic started by: DC1MC on January 21, 2018, 11:27:45 pm

Title: HP3456A with isssues, worth buying ?
Post by: DC1MC on January 21, 2018, 11:27:45 pm
This thin here form Eastern Europe (Cehia) is it worth buying, or it's done ?
What price should I offer ?
https://www.ebay.de/itm/AGILENT-HEWLETT-PACKARD-HP3456A-6-5-digit-DIGITAL-VOLTMETER-with-ISSUES-HP-3456A/272996544330 (https://www.ebay.de/itm/AGILENT-HEWLETT-PACKARD-HP3456A-6-5-digit-DIGITAL-VOLTMETER-with-ISSUES-HP-3456A/272996544330)

Thanks,
DC1MC
Title: Re: HP3456A with isssues, worth buying ?
Post by: alm on January 22, 2018, 12:06:01 am
They are good meters, assuming a stable meter that can measure DCV, ACV and resistance is what you need. It's large compared to more modern equivalent like a HP/Agilent/Keysight 34401A and will not do current, but is more accurate and stable. Look for completed listings on eBay. Last time I looked (a number of years ago), the going rate in the US was around $100, so $275 shipped for a unit with known defects strikes me as high.
Title: Re: HP3456A with isssues, worth buying ?
Post by: Vgkid on January 22, 2018, 01:28:48 am
It is a bit pricey , but the error could be a problem with the power supply. That is known to cause intermittent faults after some time.
Title: Re: HP3456A with isssues, worth buying ?
Post by: DC1MC on January 22, 2018, 03:25:35 am
Thank you all for the answers, I will make the seller an offer, and I'm really thinking that we should have a stickie with precision instruments and their worth, along eventually with defect that make them not easy recoverable.

 Cheers,
 DC1MC
Title: Re: HP3456A with isssues, worth buying ?
Post by: Conrad Hoffman on January 22, 2018, 11:32:30 am
I don't know how different these are than my 3455A, but check the low voltage and low resistance ranges. If those are your main interests, you may find them wanting. Otherwise, they're a reliable and stable performer.
Title: Re: HP3456A with isssues, worth buying ?
Post by: MadTux on January 22, 2018, 01:07:24 pm
If that 3456A was originally sold in Europe, it probably has the 50Hz line cycle frequency crystal on inguard digital board. Which makes it more desireable in EU, because sampling frequency matches line cycles. The ones from north America usually have crystals for 60Hz, so they are less acuate over here with 50Hz noise all over. These crystals have very uncommon frequency, so it's probable worth a bit of extra money....
Title: Re: HP3456A with isssues, worth buying ?
Post by: guenthert on January 23, 2018, 01:05:07 am
If that 3456A was originally sold in Europe, it probably has the 50Hz line cycle frequency crystal on inguard digital board. Which makes it more desireable in EU, because sampling frequency matches line cycles. The ones from north America usually have crystals for 60Hz, so they are less acuate over here with 50Hz noise all over. These crystals have very uncommon frequency, so it's probable worth a bit of extra money....
Shoot.  I got a HP3456A purchased in the US (hence with Option 360 for 60Hz power source), but need it now in Germany.  Does anyone have a spare option 350 or has a hint what needs to be modified?  Ah, I believe I found it in the service manual p8-35 (thanks for the hint regarding in-guard logic): the uP's clock is given there as 5.85MHz for 60Hz power line and 4.875MHz for 50Hz.  But I wonder, if it isn't easier to import an UPS with an univeral input and 110V/60Hz output.
Title: Re: HP3456A with isssues, worth buying ?
Post by: DC1MC on January 23, 2018, 03:19:10 am
If that 3456A was originally sold in Europe, it probably has the 50Hz line cycle frequency crystal on inguard digital board. Which makes it more desireable in EU, because sampling frequency matches line cycles. The ones from north America usually have crystals for 60Hz, so they are less acuate over here with 50Hz noise all over. These crystals have very uncommon frequency, so it's probable worth a bit of extra money....
Shoot.  I got a HP3456A purchased in the US (hence with Option 360 for 60Hz power source), but need it now in Germany.  Does anyone have a spare option 350 or has a hint what needs to be modified?  Ah, I believe I found it in the service manual p8-35 (thanks for the hint regarding in-guard logic): the uP's clock is given there as 5.85MHz for 60Hz power line and 4.875MHz for 50Hz.  But I wonder, if it isn't easier to import an UPS with an univeral input and 110V/60Hz output.

No !!!

Use this thread:
http://www.eevblog.com/forum/buysellwanted/wanted-4-875mhz-crystal-for-hp3456a-multimeter/ (http://www.eevblog.com/forum/buysellwanted/wanted-4-875mhz-crystal-for-hp3456a-multimeter/)