Anritsu MG3671B Vector Generator - Power supply

[ingowien]

Hi,

I got myself an old Anritsu MS3671B as it seemed to be a cheap vector generator. Unfortunately the digital modulator is unusable as it only supports some old modulation formats with just the standard data rates and does not support any kind of parameter modification. So in reality it can only be used with external data generators and the wideband analog I/Q inputs. It should provide 30MHz analog bandwidth and would be better than the 10MHz of an ESG-D with wideband AM.

But there is one annoyance I didn't recognize when I purchased it: It's rated 110..120V line voltage exclusively. Not switchable, nothing. The manual mentions that there are two different versions for 115V and 230V but nothing else. The datasheet claims that it is "100 to 120/200 to 240 Vac (switchable)" which seems to be incorrect. I wouldn't have expected Anritsu to build such limited power supplies. All my HP devices can easily be changed to various line voltages without problems (maybe except for the 66xx PSUs: you have to open them to re-connect the transformer).
-> Does anyone have knowledge if this is really true, are there different power supplies for 115V and 230V? Or are there wide range PSUs as well?

Unfortunately it seems you have to disassemble half of the generator to get the PSU out (at least the entire back panel and one side panel have to be removed). I didn't do this until now and there is only one sticker visible on the PSU. The only content is Japan 34Z113867 2.97 0052.
-> Does someone have information on these PSUs? Is it a 110..120V PSU or does it accept 110V..120V and 220V..240V?

I already placed lots of stickers on the generator to remind me that I can't use it directly but have to use one of my insulation transformers that is switchable to 115V. But I almost forgot this one time so if possible I'd like to make the generator 230V compatible. Of course the best option would be if it already is 230V tolerant.

So it would be great if somebody could clarify this, I think Anritsu wouldn't be of much help as the device is out of service since 2002.

best regards
Ingo
 

[DC1MC]

I have an Anritsu MG36336 signal generator, the power supply was switchable by opening the case and removing and resoldering a strap wire according with the  instructions printed on a protective lid inside.
The power supply itself was not easily accessible as well, but the switching plate was, because a tech may need to switch it in between voltages.
I personally don't think there are two different models of power supplies, I just believe that they've put the switch inside the case to avoid issues and eventually suck a bit of cash when doing the conversion by an "authorized representative".
I would say open the case and look around to see if you find the hidden switch/lid, and eventually post some pictures.

 Cheers,
 DC1MC

[ingowien]

Hi,
thank you for your fast response. Unfortunately e-mail notification hasn't worked, so I have seen it just some minutes ago.
I haven't found an obvious switch, maybe something is hidden on the bottom side of th ePSU where the output cables are connected (3 or 4 IDC connectors). I only had access to top and right side (PSU is on the right side seen from the back of the generator), inner side, front/back and bottom are covered by other parts. I'd hope that there is a wide range PSU installed and just the label on the case is incorrect. Otherwise this would be an extremely bad design. On the other hand why would the label on the case and the service manual be incorrect. I'll open the generator once again when I have more time and check this in detail.
best regards
Ingo
 

[DC1MC]

Hi,
thank you for your fast response. Unfortunately e-mail notification hasn't worked, so I have seen it just some minutes ago.
I haven't found an obvious switch, maybe something is hidden on the bottom side of th ePSU where the output cables are connected (3 or 4 IDC connectors). I only had access to top and right side (PSU is on the right side seen from the back of the generator), inner side, front/back and bottom are covered by other parts. I'd hope that there is a wide range PSU installed and just the label on the case is incorrect. Otherwise this would be an extremely bad design. On the other hand why would the label on the case and the service manual be incorrect. I'll open the generator once again when I have more time and check this in detail.
best regards
Ingo

Hi Ingo, next time you now the drill: pictures, pictures, and more hi-res pictures, no corner left behind .

 Cheers,
 DC1MC