DSE Q1803 $128 CRO

Phil Allison · 2006-05-28T04:51:10+00:00

Hi to all,Picked up one of these 10MHz, single beam CROs from my local DSE store last Tuesday - there were none on display and the staff seemed unaware of its existence. The unit comes in a carry box, well packed with IEC mains lead, 10:1 probe and small handbook written by DSE staff.Using a bench sine/ square generator and frequency counter when back at home, I found my unit met published accuracy specs - time base speeds being particularly accurate.The *green* trace on the 75m dia tube face is particularly sharp and geometry is very good all over the (external) graticule.The vertical and horizontal positioning pots allow the pattern to be moved right off the screen without visible limiting - so the deflection amplifiers have adequate headroom.The internal (Y) synch appears to function well as does the external and LINE synch inputs. There is an X-Y mode that works fine too. There is no "trace rotate " control, but two screws on the rear can be loosened to allow the tube and hence trace to be lined up with the graticule OK.Now for the insides:-----------------------With the vinyl coated steel sleeve slid off, there is a nice surprise. This little CRO is *very* well made - reminiscent of the way Aussie firm BWD built their famous CROs.There are no SMD, all parts are "garden variety" - ie TO92 pack transistors, TO220 regulators, a couple of fets and 3 bog standard ICs. There is one large PCB for the PSU, deflection and synch circuits while a smaller one at the front covers the vertical attenuator, input pre-amp and time base circuitry.Both sides of these (single sided, through hole) PCBs are fully accessible for servicing !A very neat, 20 VA, R-core transformer powers the CRO with a ferrite HF inverter supplying 1200 volt DC to the tube. All internal voltages remain regulated down to 200 volts AC input.The 75mm tube is covered in a black, very snug fitting, full length MAGNETIC SHIELD !! This is practically unheard of in a low cost CRO and means the...

May 28, 2006 43 Replies

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Bob Parker 20 years ago

Ah, thanks for the update and explanation about why you've still got the Q1803. Have you had any tempting offers for it yet? It would still be far more useful to me than a BWD521 which won't trigger and often loses one channel. Belated birthday wishes for a few months ago. :-) Yeah, that stable of girls and landlording commitments wouldn't leave you with much time. You have my sympathy. I'll send you a quick e-mail regarding the CRO, and give the denizens of this NG some peace.

Cheers Bob

model

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Wayne Reid 20 years ago

MuMetal?

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Phil Allison 20 years ago

"Wayne Reid"

** Doubtful.

More likely GOSS transformer lam material.

....... Phil

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Wayne Reid 20 years ago

I should have put one of these things on the post... ;)

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