I picked this up yesterday at RetroTech, I had been on the lookout for a wow & flutter meter for a while, especially since getting my 8-track, cassette players. This one called to me as it offered so much more in one unit. The service and operating manual are in the data library, for now, some brief specs. No doubt, I'll have some fun figuring out how to use this!
OSCILLATOR
Frequency Range 15Hz to 150kHz in four ranges. Frequency Response Flat within ± 0.2dB over the range 15Hz to 150kHz
Distortion
Less than 0.025% at 1kHz,Less than 0.08% over the range 100Hz to 20kHz. Maximum Output Level,3V (approx.) into open circuit Not less than +8 dBm into 600 ohm load. Output Attenuator;Coarse- Six steps of 10dB, Fine- Continuous over range of 15dB approx.External - Fixed 40dB. Output Impedance; Independent of frequency dependent on setting of output attenuator coarse control:always less than 450 ohms. From external 40dB attenuator 47 ohms
WOW & FLUTTER OSCILLATOR
Frequency 3.15kHz, Output Level 350mV approx. Output Impedance 220 ohms approx.
MILLIVOLTMETER
Frequency Response Flat within ± 0.2dB over range 10Hz to 150kHz. Accuracy within ± 2% f.s.d. over range 30Hz to 20kHz
Sensitivity 1mV to 100V f.s.d. in 11 steps of 10dB
As you'd expect from Ferrograph, it oozes quality of design and construction. The internals look in remarkable condition, sadly the top panel has some gouges, not sure if I will be able to rectify that.
I will have to keep my eye out for the companion unit, the ATU1 (Auxiliary Test Unit)
Good for you! These were nice in their time but as you imply, they are most useful for vintage kit.
I have a set with the ATU1, which was useful for interfacing with balanced kit. It also had switched filters and attenuators, useful for calibration.
Nothing like this will ever be made again, as (apart from I/O) it can all be done in software.
Enjoy!
That's nice, but not as nice as my Radford distortion measuring set 😉 One part of the two parts is driven by two PP9 batteries so there's absolutely no chance whatsoever of mains hum being introduced.
Which reminds me, I must resurrect the HP Audio analyser I own.
I had in the workshop the Sugden audio test units. Audio osc, filter and meter, three separate items using PP9 batteries.
Not as expensive as the Radford or other makes and perhaps a bit more fiddly to use but a decent setup for a very small workshop. The boss always provided the best test equipment the shop could afford.
That's nice, but not as nice as my Radford distortion measuring set 😉 One part of the two parts is driven by two PP9 batteries so there's absolutely no chance whatsoever of mains hum being introduced.
Which reminds me, I must resurrect the HP Audio analyser I own.
Is one of them an LDO3? I found that when I removed the base panel on mine that where the screened cable touched the yellow plastic cases of the range-setting capacitors, the latter had gone soft and gummy and foamed-up, presumably caused by the cable insulation plasticiser reacting with it. Fortunately, the blight hadn't gone as deep as the foil sandwich but was still a little alarming. I re-dressed the leads and caps to be well clear of each other.
As an update to my previous post I have found a picture of the Sugden test set, it worked very well.
