Siglent SPD3303D review

[jimjam]

What and where did you get it from?

[ScottyAU]

Post in other Thread

 

[ScottyAU]

Triotest heard back from Siglent - they said they fixed the issue in December.

Triotest assure me the current stock will include this fix!

Scotty

[TRIO Test and Measurement]

Hi folks, as Australia's sole Siglent authorised distributor, I'd like to set some minds at ease.  We have received quite a few emails asking if our stock of SPD3303D is the latest version and has this voltage-transient bug fixed.  Siglent has confirmed in writing to us that it is fixed in all our current stock.

We have stock as of today of all three of the PSU's in this family.   Links are here and includes the new SPD3303C for those that don't need the graphical display on the "D" model.
http://www.triotest.com.au/shop/en/search?controller=search&orderby=position&orderway=desc&search_query=siglent+spd&submit_search=Search

Check-out the new SPD3303C.  It is great value. 
http://www.triotest.com.au/shop/en/dc-bench-supplies/3448-siglent-spd3303c-195w-dc-power-supply-30v-3a-x-2-25v33v5v3a-x-1-10mv-step.html

Also, if anyone wants a bargain oscilloscope, we are clearing-out the standard screen size  150MHz   SDS1152CM for just $395.00 (+gst for Aussies). These are new with full a Siglent 3 year warranty supported in ANZ by us.
http://www.triotest.com.au/shop/en/siglent/2952-siglent-digital-storage-oscilloscope-150-mhz-bandwith-2-channel.html

Cheers!

[ScottyAU]

Really appreciate the reply TRIO Test - thanks very much!

[Siglent]

As early as last year, we have fixed this problem, please rest assured purchase.

[FrankBuss]

As early as last year, we have fixed this problem, please rest assured purchase.

Thanks. In which hardware version was it fixed, if someone wants to verify it? When I click on the version button on my device, it shows "hardware version V1.1".

[Siglent]

the hardware is still V1.1, but we have corrected the mother board version.  the Prior version is SDY8.007.038D, now it has been modified to SDY8.007.038E ( as the figure showed)

[ScottyAU]

My Siglent arrived today.  Bit hesitant to open it up just yet to check the board  Display says Software 1.01.01.01.06 Hardware V1.1

I've hooked it up to the scope and done a few tests (screens below).  All tests done on the 3rd connector set to 5v with a load resistor across the 3rd output.

1) Cold power on
2) Shorting the 3rd connector
3) Removing the short on the 3rd connector

Be interested in peoples thoughts...

[jimjam]

Is that a 1V - 1.5V spike on power on?

[ScottyAU]

Unless i'm doing it wrong (which is entirely possible) - yep!

[jimjam]

Unless i'm doing it wrong (which is entirely possible) - yep!

So much for that....

I guess it's still better than Rigol DP832:
https://www.eevblog.com/forum/testgear/found-bug-in-rigols-dp832/msg348106/#msg348106

[ScottyAU]

That's only on a  cold boot - turning the whole supply on.

The channel on/off does't spike.

Shorting the output does a little.

Frank i'd be interested in your thoughts mate if you read this - or Siglent.

[FrankBuss]

The 1 V overshoot after the short is more than twice as much as I measured, as you can see here: https://www.eevblog.com/forum/testgear/siglent-spd3303d-review/msg299246/#msg299246 Still better than without the fix, which had 7 V overshoots (so up to 12 V), so I guess you have a new version. I wouldn't care about it, it is below absolute maximum limits of nearly all attached 5 V electronics, like old TTL ICs, or an Arduino.

Can you compare it with ch1 and ch2? If there are no overshoots, you can be sure that it is not your measurement setup, like ground loop, impedance mismatch (but this is unlikely with 1 ms per division), to long cables etc.

But it is strange that you have some voltage on cold power on, I don't see this on my patched device.

[nowlan]

would 1-1.5v kill anything though?

[ScottyAU]

Thanks for the feedback Frank.

I can confirm there is no overshoot on channel 1 or 2 (just tested).

I'm happy

[FrankBuss]

would 1-1.5v kill anything though?

For example the datasheet of the ATmega128A says 6 V absolute maximum rating for operating voltage, but the chip doesn't know the datasheet and I'm sure it doesn't matter much if there is a short milliseconds long overshoot to 6.5 V. Once for a PIC I swapped Vcc/GND on a breadboard, wondering why it got really hot, and the chip survived it. A random datasheet for a 74LS00 says 7 V for supply voltage as its absolute maximum rating.

But I would suggest to connect your sensitive circuits only to one of the current limited channels anyway, and use channel 3 just for more robust things, like a fan.

[ducatistou]

Hi,

Happy to join you for my first post on EEVBLOG, my favourite electronics blog and Youtube chanel.
I'm a french electronics and radio listener amateur, so excuse my approximative english !

I have an issue with my new PSU Siglent SPD3303D. Since i have installed the PSU in my radio shack, i have some RF perturbations in my RTL2838 SDR Radio with SDR-Radio V2.2 console

It's a brand new SPD3303D with last firmware and hardware I suppose because I don't have overshoot at turn on or <1 V

The PSU is well grounded, the RTL dongle is very far from the PSU (more than 10 meters) in an other room, but the PSU is not so far from the antenna with a HF LNA, 4 m high, and 15m of low loss cable to the RTL dongle

When the PSU is on and output chanels off, everything is ok
When I turn on a chanel I have a cyclic perturbation and when I turn on the 2 chanels I can hear the same perturbation at half frequency than the previous one. These interferences appear on single, serial or parallel mode

You can see the waterfall screenshots and the audio files here http://1drv.ms/1t2OKzL

I'll try to contact the support supply

The output signal on scope is not so bad with very few interferences in digital mode

Thank you if you have any suggestions

BR

Eric

[FrankBuss]

That's interesting, because it is a linear power supply and not a switched-mode. Maybe it is some noice from the CPU board? I can't see the frequencies, but looks very regular, like the harmonics of the CPU clock.

Do you see these interferences with cables on the DC output connected or with no cables, too? If it is with cables, maybe you can fix it by adding some ferrite beads to the output, which might need some PCB scratching and soldering. If it is without cables, it might need some serious rework, like shielding the logic board, or maybe it injects noise in the mains input, because of insufficient filtering.

[ducatistou]

Thank you for your reply

Siglent EU support has sent my request to their engineers, fast support answer ! Wait now for engineers answer 

I can see interferences with or without cables on DC output, may be a little bit stronger with cables.
Here is an exemple with SDRSharp near 120 Mhz where I guess the interferences stronger

I plugged the PSU on a Shaffner main filter with no difference, but it is a more a common than a differential RF filter

I also think it comes from the CPU board, but why only when an output is on    

PS : this is an exemple without LNA, direct antenna (external discon) on RTL dongle

[ducatistou]

I made an other test :

I put the Siglent PSU near and very close to the RTL dongle and computer and surprisingly i noticed no interferences ! The dongle is shielded in a little PCB box

I put back the PSU in the shack far from tuner and interferences went back thru antenna and/or coax i suppose

Unfortunatly ... i use the PSU in the shack not in the radio room, then i can't power the LNA with the Siglent !! 

[FrankBuss]

Looks like it is related to how near it is to the antenna. But is there a reason why you are using a EUR 300 lab power supply to power a LNA? There are much cheaper linear power supplies without any microcontroller.

[ducatistou]

  thank goodness, it's not for the LNA ! But as it is on for my electronics projects and hacks it could do so ... but not. One of my old free homemade power does obviously better ... and i have to switch it off when i'm listening SDR. I like this PSU for what it can do, design and accuracy, but as you say for $300 i didn't expect such annoying issue in HF domain, hope it will not interfere in my next radio projects

[ducatistou]

Here is the Siglent's engineer answer :

"Hi Eric,
I don’t know much about the RF perturbations, So I cannot understand it well.
One explanation is because there is a feedback circuit which produces crosstalk while you opened the output channels.
If you have any doubt, please feedback."

 

[artelse]

Hi,

Have been on the lookout for a new PSU and this Siglent catched my eye. What I am wondering about, is there a real benefit to have an LCD screen on the device instead of just a nice LED panel like on the SPD3301C version?

Thanks!