Recent Posts

1

Power/Renewable Energy/EV's / Re: 5 out of 6 vendors are scamming people with wrong crosssection of cables

« Last post by f4eru on Today at 02:15:16 am »

I measured via visual and electrical methods, so there is no doubt about my measurements.

Pleaae publish your measuremenets.

2

Power/Renewable Energy/EV's / Re: 5 out of 6 vendors are scamming people with wrong crosssection of cables

« Last post by thermistor-guy on Today at 02:14:16 am »

...
   it's the same story as my Chinese made trailer, it will almost meet the stated load but there is NO safety margin.

There's a Chinese EE located near me, running a transformer rewinding business. He's from Shanghai. Many years ago, he told me that
Chinese electronics are made to a price, and they will only just meet spec. (if at all).

He went on to say that, unlike US or EU equipment, Chinese-brand equipment will not have any overload capability, not even
short-term overload.

3

Test Equipment / Re: Agilent 54845A Failing all trigger self tests

« Last post by MarkL on Today at 02:13:53 am »

I've been following your progress on this thread, but I can't really add much since I don't have this scope.

However, I will point out that the Agilent 16533A and 16534A scope cards for their logic analyzer line (which I do have) uses the same Logic Trigger 1FJ9-0002 ASIC or 1821-4786 carrier board, and the same Time Base 1SE6-0056 ASIC.  Other scopes from that era also use this chip set.  I'm sure HPAK re-used this design as much as they could.

I think you're right that the Logic Trigger carrier card replaced the ASIC at some point for unknown reasons.  The 16533A/16534A cards also exhibit this change in their lineage as well.  I have some of both types and the behavior and specifications are identical.  However, I don't think the 1821-4786 carrier card is a complete drop-in for the 1FJ9-0002 ASIC because there are other changes in that area on the 16533A/16534A cards between the two versions.

I'm just pointing this out since these cards might be a possible source for ASIC replacements, if you should determine you need one.

I don't want to send you on a wild goose chase since you are working on a completely different device, but I can also say the scope cards have a history of bad resistors, either completely open or wrongly high value.  I've had a couple of bad termination resistors, one of which was on a clock line which caused multiple errors during self-test.

I've also bad resistors on the output setting pins of local voltage regulators that caused the wrong voltage to be output.  In one instance, it was on a regulator used to supply ECL termination networks on the card, again causing multiple and seemingly unrelated self-tests to fail.

4

Repair / Re: Mig welder wire feeder controller board not working

« Last post by TERRA Operative on Today at 02:11:50 am »

Yeah, basic, non critical MIG welding on mild steel is pretty forgiving. I never really understood why some people end up with no penetration on their bird-poop welds....

TIG does need a clean surface, but there are welders that provide cleaning settings (AC balance IIRC?) especially for aluminium alloys etc, but nothing beats a pre-cleaned surface.

5

Beginners / Re: Automatic golf ball dispenser

« Last post by BTO on Today at 02:11:21 am »

The final prototype. Check this out.
https://youtube.com/shorts/KOmL9WKCEq0?si=3pFnC7feHF5k9J2u

- Checked it out
- Had the priviledge of leaving the first comment 

Bunnings bucket huh ? I suggest a modification so that every 10 golf swings, it dispenses a bunnings snag and can of coke.

Now, that aside, it seems to work well, How are you finding it thus far, any issues ?
Also... Since it's purpose is to setup a golf ball, What about when you missed and the ball fell off the T , Shouldn't it also
dispense it then ? or... You're not gonna worry about that ?

but yeah, can you see any issues with it, Especially with Alignment, as you stated before , So can you say, Get through 100 balls without it
falling out of alignment with the T ?

6

Test Equipment / Re: Siglent SDS2000X HD, 12bit, 2GSa/s high definition oscilloscope serie.

« Last post by egonotto on Today at 02:09:58 am »

Hello,

I have the impression that the SDS2000X HD always has a small downward dent in the left in channel 1 when the input is open in auto-trigger mode.


Best regards
egonotto

7

Manufacturing & Assembly / Re: Fellow LPKF equipment users?

« Last post by Jay_Diddy_B on Today at 01:59:12 am »

Hi! I'm a Protomat S42 owner, hopefully soon to be operator.

@rodsolder, my machine came second-hand with a few boxes from Think & Tinker's bits, available from Colorado, USA, at https://www.precisebits.com/ . I haven't gotten my machine up so can't vouch for them, but they are cheaper than LPKF bits.

I have been using these bits for the last 10 years in my protomat c60. They are great. Highly recommended.

The c60 doesn't use the depth collars so the bits have to be the correct length. Some of the low cost bits I have bought from eBay have been the wrong length.


Regards,

Jay_Diddy_B

8

Beginners / Re: Automatic golf ball dispenser

« Last post by Maclarkson on Today at 01:55:34 am »

The final prototype. Check this out.
https://youtube.com/shorts/KOmL9WKCEq0?si=3pFnC7feHF5k9J2u

9

Test Equipment / Re: Siglent SDS2000X Plus Hack

« Last post by Vertical Loop on Today at 01:52:29 am »

Updated script. Easier to read, no capital keys, added some comments. Worked for me still.

```
import hashlib

# Scope identification found in the system info tab
# to find this, touch the utility tab on the top left of the SDS screen.
# The dropdown will have a "Menu" option. This will open a dropdown on the right,
# select the (i) System Info from the dropdown.

# The "Scope ID:" hosts this variable. Remove the hyphens and keep the value lowercase.
SCOPEID = 'agy4mj75hf6jnd52'


# The model is a generic variable, not a specific model number, in this case the SDS2000X+,
Model   = 'SDS2000X+'

bwopt = ('100M', '200M', '350M', '500M', 'AWG', 'MSO', 'FLX', 'CFD', 'I2S', '1553', 'PWA', 'MANC', 'SENT')

hashkey = '5zao9lyua01pp7hjzm3orcq90mds63z6zi5kv7vmv3ih981vlwn06txnjdtas3u2wa8msx61i12ueh14t7kqwsfskg032nhyuy1d9vv2wm925rd18kih9xhkyilobbgy'

def gen(x):
   h = hashlib.md5(
      (
      hashkey + (Model+'\n').ljust(32, '\x00') + opt.ljust(5, '\x00') +2*((SCOPEID + '\n').ljust(32, '\x00')) +
      '\x00'*16).encode('ascii')
   ).digest()
   key = ''
   for index, b in enumerate(h):
      if (b <= 0x2F or b > 0x39) and (b <= 0x60 or b > 0x7A):
         m = b % 0x24
         b = m + (0x57 if m > 9 else 0x30)
      if b == 0x30: b = 0x32
      if b == 0x31: b = 0x33
      if b == 0x6c: b = 0x6d
      if b == 0x6f: b = 0x70
      # every four characters print a space
      if index and index % 4 == 0:
        key += " "
      key += chr(b)
   return key
   
for opt in bwopt:
   print(f'{opt}: {gen(SCOPEID)}\n')
```

10

General Technical Chat / Re: Relay trigger when voltage above 13v

« Last post by Andy Chee on Today at 01:46:58 am »

I think you’re after a hysteresis circuit i.e. turn on relay as voltage rises above 13V, turn off relay as voltage drops below 12V.

Alternatively, perhaps you’re after a monostable “reset” circuit i.e. turn on relay as voltage rises above 13V, relay remains on until power is removed.