Square wave inverter for Analogue Oscilloscope

[Hex173t]

I did a search for oscilloscopes and square wave inverter and found it addressed for use with a Rigol model (thread Re: Using rigol DS1052E with Kensigton inverter back in Feb 11).  Is there any difference in the analogue scopes such as the Tek 468?  Sure would make me sad to kill it accidentally.

Bill

[Simon]

you really want a sine-ish inerter if the scopes psu works off a traditional transformer

[Zero999]

I haven't done any tests with 'scopes but I'd suspect analogue would' be worse than digital.

Most inverters nowadays at least modified sinewave. I don't think I've seen a squarewave inverter apart from the homebrew variety. Modified sinewave is slightly better but not much. The worst thing with squarewave is the peak voltage is equal to the RMS voltage so a 230V squarewave may not have a high enough peak voltage to power an SMPS which would be designed for 230VAC with a peak voltage of 325V. A modified 230V sinewave has a peak voltage of 325V and an RMS voltage of 230V so will be able to power an SMPs or an incandescent lamp with no problem. Another issue is the harmonics and RFI which will a squarewave than a modified sinewave.

The reason why a digital 'scope will probably be better is that its power supply is switched mode so will be rectified to 325VDC anyway. There should be a good RFI filter to remove the harmonics generated by the SMPS anyway. An analogue 'scope will have a transformer connected to a rectifier and very little RF filtering.

[alm]

My guess would be the same as Hero, a typical linear supply has much less RF filtering, since 50/60Hz ripple tends to dominate with a good quality mains supply.

Be sure to consider the safety implications if your inverter doesn't supply the scope with a reliable and low-impedance ground connection, it would be sad to kill yourself accidentally.

[Hex173t]

Thanks for the responses!  The consensus seems to be don't use this type inverter on an analog scope.

Bill

[tekfan]

Tektronix made a squarewave inverter with a battery pack that was designed for the 400 series.

http://amplifier.cd/Test_Equipment/Tektronix/Tektronix_other/1105.html


BTW the Tek 468 is actually a digital storage scope

[Hex173t]

Thanks Tekfan, beauty link. 

And that the 468 is a DSO was a draw when I was reading on what scope would suit my needs.  And the work out from moving it around is healthy   Sucker is heavy.

Tektronix made a squarewave inverter with a battery pack that was designed for the 400 series.

http://amplifier.cd/Test_Equipment/Tektronix/Tektronix_other/1105.html


BTW the Tek 468 is actually a digital storage scope