Advance OS2000 -2100

[WME_bill]

Advance OS2100 oscilloscope.
I have been asked for information about the Advance OS2000 series of oscilloscopes, current about 1970.
They were interesting in that they used a constant voltage transformer for the power supply, so no regulated power pack. The CVT was made by the Advance power supply unit up in Wrexham. Now an entirely separate company.
The snag is that the mains operating frequency is vital, and different models were made for USA and UK/Europe markets.
Later models, the OS3000 series and OS250/300 etc all reverted to using conventional regulated power supplies.
I attach a sales leaflet with 1970 prices which has appeared in my pile of papers. I have manuals for both main frames, the usual plug-ins and the Brimar cathode ray tubes used. They were nice scopes I believe.
wme_bill