The PHILCO Phorum

O-scope questions:

I just picked up a Simpson Handicsope because I liked the vintage look and I want to learn how to use an O-scope.

It needs a restoration like any 50's vintage device. One tube tests bad and all the caps are original. A manual was hard to find but one is on the way and I hope it includes a schematic.

It has no probe and I am wondering what to get. Online info says the input resistance is .1meg@ attn. x1 and .5 Meg @attn x100. Capacitance 40 uuf @ attn x1 35 uuf @ attn x100.
It has banana plug inputs.

Any clues on where to start looking for probes?

The old sales info on this scope says:

Frequency Response of Vertical Amplifier: From 15 cycles/see
to 100 Kc/sec, flat within ±1 db; 6 db down at 250 Kc/sec; usable
to 1 Me/sec.

Maximum Vertical Deflection Sensitivity: 30 Millivolts RMS/
inch.

Frequency Response of Horizontal Amplifier: From 15 cycles/
see to 20 Kc, flat within ±1 db; 6 db down at 100 Kc/sec.

Maximum Horizontal Deflection Sensitivity: 0.7 volt RMS/inch.
Z-Axis Sensitivity (Voltage Required to Extinguish Beam):
20 volts RMS.

Calibrating Voltage (at 117.5 VAC power source): 1 volt pop
±10%.

Maximum Input Voltage: 400 volts peak.

Input Resistance: 0.1 Meg (at atten. x 1); 0.5 Meg (at atten. x 100).

Input Capacitance: 40 uuf (at atten. x 1); 35 uuf (at atten. x 100).

Sawtooth Sweep Range: 15 cycles/see to 80 Kc/sec.

Power Consumption (at 117.5 volts AC): 50 watts ±10%.

If you want to go with an old skool probe something like this one would work.
http://www.ebay.com/itm/Vintage-Heathkit...7675.l2557
Be careful as Heath made two that look the same one is a demodulator probe for it's signal tracer and the other is the low capacity scope probe.

GL

From what I can understand...most online sources seem to indicate that almost any modern 1X probe will work for these low frequency scopes...as long as the capacitance compensation range is correct.

I'm only planning on using it on old radios so high frequency testing isn't a concern.