Recent Posts

1

Metrology / Re: Symmetricom S200 Teardown/upgrade to S250

« Last post by DavidKo on Today at 08:22:06 am »

I think that this is already described in pages before. Your unit will not work on GPS. You need GPS module update. Same was on my side, after installation of Heol design module the unit is locking to GPS. I do not remember the exact rollover date when Furuno stopped working, but I think that it is also mentioned in the thread.

2

Test Equipment / Re: Siglent SDG1000X Waveform Generators

« Last post by tautech on Today at 08:21:00 am »

I just received my SDG1032X today.

I was looking for an option to limit the leves, but i only could find amplitude limit. I guess am just blind?

P102
https://int.siglent.com/u_file/download/22_06_23/SDG1000X_UserManual_UM0201X-E01E.pdf

3

Other Equipment & Products / Re: CFW for KSGER/Quicko STM32 Soldering Stations

« Last post by spleenharvester on Today at 08:11:10 am »

That 431 for me looks more like Schottky diode, I may be wrong though. 5 legs part below seems to be lm321 opamp to sense tip current. But that schematics looks strange. I can't find feedback circuit.

As for your broken display... At least you have good case and PSU. You can buy replacement controller board and have working soldering  station ))

For earth connection I just bridged E and - on PSU board with blob of solder.

UPD:
431 could be TL431 voltage reference, yepp. But anyway I can't understand how that part of schematics is intended to work )))

It's entirely possible I've just gotten it wrong    I'll have another look, it took me several attempts to trace that one

4

Projects, Designs, and Technical Stuff / Monitoring battery voltage -- low-leakage voltage divider?

« Last post by ebastler on Today at 08:10:23 am »

In an STM32-based project which uses a LiPo battery, I would like to measure the raw battery voltage to get a rough indication of the remaining charge. Since the battery voltage is higher than the STM32's regulated supply, I cannot connect it directly to an analog input.

The obvious solution of using a resistive voltage divider is not great, since it will draw non-negligible standby current: The highest input impedance of the Sigma-Delta ADC input is around 1.5 MOhm (during conversion, for lowest gain and clock frequency), hence a voltage divider would need to be around 100 kOhm or lower.

What are my options here?

• A high-impedance divider with a large buffering C? (Input impedance without an active conversion is not specified, but should be very high, and I don't need to run the conversion often.)
• An op-amp buffered voltage divider? (But then standby consumption of the op-amp becomes an issue...)
• Are there battery charging ICs which provide a Vbattery/2 output for easier monitoring?
• Any other ideas?

Which approach would you prefer? Which ones are terrible ideas? Thanks for your comments!

5

Beginners / Re: Charging voltage for NiMH battery

« Last post by beanflying on Today at 08:07:00 am »

I thought Siwastaja is the THIRD pompous self righteous dill here?

As much point of you making a critique of my post I guess 

Guess what, at least I didn't include the spam link in my post like a mindless drone.

So now you make a second post to justify your position. What a banker!

6

Beginners / Re: Powering DC Motor from Solar panel

« Last post by beanflying on Today at 08:03:22 am »

Have a good trawl through the links and the rest of site here https://www.modelsolar.org.au/tech-support-old/design-guide-student-design Way back when my Dad and a Uni Lecturer set this up as a Statewide program.

The MPPT has become a bit of a must to be competitive as pulling the Solar array to a low voltage costs way more potential Watts in than the MPPT consumes. There are some curquit diagrams out there online but most competitors went the easy option and one of these https://www.scorpiotechnology.com.au/starter-solar-challenge-kits

Typically Faulhaber or similar quality motors get used by the winning cars.

7

Beginners / Re: Charging voltage for NiMH battery

« Last post by magic on Today at 08:01:34 am »

I thought Siwastaja is the THIRD pompous self righteous dill here?

As much point of you making a critique of my post I guess 

Guess what, at least I didn't include the spam link in my post like a mindless drone.

8

Test Equipment / Re: Program that can log from many multimeters.

« Last post by Gertjan on Today at 07:58:32 am »

V2.44 is up
       ...
   Fixed: ProLogic GPIB uses lowercase control clr/llo/loc/trg commands

Hi HKJ,

I re-tested with the official Prologix GPIB->USB Controller (with latest firmware: v6.107).
I can confirm that with the lowercase control commands the Prologix now performs flawless in TestController. 

Actually, it would be a good idea to change the control commands for AR488 to lowercase too. After all, it is a clone of the Prologix.
AR488 tolerates uppercase, so works flawless at the moment. But who knows about future versions, clones of clones etc...

regards, Gertjan.

9

Vintage Computing / Re: Getting an MVME320B (Motorola VME HD controller) working

« Last post by LittleFrog on Today at 07:57:57 am »

Morning Marco.  Amazing.  I'm so grateful.  Thanks.

10

Test Equipment / Re: Siglent SDG1000X Waveform Generators

« Last post by eTobey on Today at 07:57:56 am »

I just received my SDG1032X today.

I was looking for an option to limit the leves, but i only could find amplitude limit. I guess am just blind?