Solatron 'Resolved Component Indicator' questions. / General Chatting / Forums

Forums

4hv.org :: Forums :: General Chatting

« Previous topic | Next topic »

Solatron 'Resolved Component Indicator' questions.

1 2 next

Move Thread

LAN_403

Ash Small

Sat Oct 26 2013, 03:25PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

I picked one of these up in the local 'flea market' yesterday, along with a few other 'goodies'.

Does anyone have any idea what it does, or what I can use it for?

I get the idea it's something to do with 'phase lags', so is it something to do with matching circuits?

I've tried googling 'resolved component indicator' but, as yet, I've not turned up anything of any significant significance.

testtest

Sat Oct 26 2013, 04:57PM

Registered Member #3271 Joined: Mon Oct 04 2010, 02:29AM
Location: Canada
Posts: 159

Phase sensitive voltmeter. Useful for mechanical transducer, torsional systems measurements, etc... Even for long cables or anything where the voltage application and resulting measurement are not in phase. For example looking at phase flip before and after hitting a peak voltage/system resonance.

instruction manual available at:

about midpage.

Ash Small

Mon Oct 28 2013, 12:20PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

Thanks for the link, Rich. The only reference to one being used, that I've so far found, seems to indicate that a dual beam 'scope will do the same thing much more simply:

"The strain-gauge output was taken both to the Solartron
Resolved Component Indicator and to the Tektronix Dual-Beam Oscilloscope, this latter also
monitoring the input frequency. Although it can only be used with a sine-wave input and thus not
with jet noise, the advantage of the Resolved Component Indicator was that by measuring phase
change as well as signal magnitude it was possible to locate a resonant peak even if the transducer
were on a node. This analysis became rather lengthy due to the very large frequency range to be
covered and was replaced by noting the magnitude of the deflection of the output signal on the
oscilloscope."

Is there anything this can be used for that can't be done with a 'scope?

Telford Electronics have quoted Â£20 for "Solartron VP250 Operation & Service Manual with A3 Drawings,Circuits etc."

Is this of any 'real' use, or should I just strip it for parts?

(I suspect that even if I put it on Ebay as 'tested and working, with manuals, etc.' I won't get a lot of interest.)

testtest

Mon Oct 28 2013, 07:01PM

Registered Member #3271 Joined: Mon Oct 04 2010, 02:29AM
Location: Canada
Posts: 159

My guess, if the top scale major division is one degree (from your photo) and you can resolve 1/10th of that is that a dual beam scope may be hard pressed to resolve with that kind of precision by eye measurements. In the "old" days like with my Tek 545 with a Type 53 plug-in the chopping error with trigger uncertainty would not be able to do it.. Superposing the two traces to see half a degree lag would likely look just like a fatter trace, not a useful measurement. Tek also had a true dual beam (two guns) sharing the same horz deflection to avoid the delay/chopping errors. Of course with today's digital scopes this point is moot!

A 20 deg phase shift would be easy to do with a scope or a Lissajous x-y figure after adjusting the amplitude of each channel. Still the measurement would be eyeballed.

It is a nice instrument that probably merits a period correct restoration if the insides are good. If you get into designing audio cross-overs and feedback circuits or doing compensation circuits for seismographs (although the frequency range is a bit low end limited for that), for example.

My first reaction if I came across one of these would be to place it next to my HP 332A distortion meter and the Phillips GM2317 low distortion oscillator on my work bench. They date from the days I was involved designing very high fidelity speakers and amplifiers. Now the weak link in my audio setup are my ears!!

Nostalgia yes. If you want to keep everything analog, yes. If you just want function, meh.... just buy a high end digital scope.

Ash Small

Mon Oct 28 2013, 10:50PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

richnormand wrote ...

Nostalgia yes. If you want to keep everything analog, yes. If you just want function, meh.... just buy a high end digital scope.

Well, I can't afford a 'high end digital scope', and I'm not sure I have a need for one, at the moment anyway.

I was wondering if it had any use for matching circuits, as, if I remember correctly, there are two different 'quantities' that require matching, the frequency (phase), and the impedance, (I may have to go back and find my first thread on this forum to refresh my memory).......Could this be used for tuning a matching circuit for an RF plasma source? (I realise I'd still need other instruments as well)

I realise I've not explained this very well, it's pretty busy here at the moment, and I need to refresh my memory.

EDIT: There are two 'components' that require 'matching', could this be used to 'resolve' one of them?

testtest

Tue Oct 29 2013, 01:17AM

Registered Member #3271 Joined: Mon Oct 04 2010, 02:29AM
Location: Canada
Posts: 159

Since the front panel on your photo indicates 20 c/s (Hz) to 20k I am afraid direct RF injection is out of question for this unit. It seems to cover the usual audio range. But if you use it to FM modulate the driving RF circuit you could use it to read the phase shift through the resonance. Pretty awkward way to do it though. A measurement of RF a standing wave reflection ratio (SWR) is a more direct way to match impedance and maximize forward power (look at ARRL handbook).

Ash Small

Tue Oct 29 2013, 01:25AM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

richnormand wrote ...

Since the front panel on your photo indicates 20 c/s (Hz) to 20k I am afraid direct RF injection is out of question for this unit. It seems to cover the usual audio range. But if you use it to FM modulate the RF circuit you could use it to read the phase shift through the resonance. Pretty awkward way to do it though.

Ok. I think that in the link I posted above they were only using it in the audible range, so that makes sense.

I won't spend money on the manual, at least until I've looked inside it, although a schematic may be useful if I decide to strip it for parts.

Sulaiman

Tue Oct 29 2013, 01:39PM

Registered Member #162 Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3140

I can't think of a use as-is,
the first thing I'd do is open it up and directly test the moving coil meters,
usually the bearings can be re-adjusted for a free movement.
You'd probably get more on eBay for two large meters than for such a redundant piece of equipment.

For r.f. you can get a new usb Vector Network Analyser for a few hundred pounds.

Ash Small

Tue Oct 29 2013, 01:46PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

Sulaiman wrote ...

You'd probably get more on eBay for two large meters than for such a redundant piece of equipment.

That's exactly what I was thinking, but I'll probably hang onto them and use them myself for something.

I'm also interested to see what else is in there.

(I wouldn't have decided to strip it if it had any real use/value 'as is'.)

Proud Mary

Sat Nov 02 2013, 03:44PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

This apparatus was used to map acoustic stress in relation to vibrational resonances, standing waves, nodes in airframes. It was used in both wind tunnel design, and in looking at questions around engine vibration propagation through an airframe.

The external reference signal source might be, for example, an engine tachometer, or it might be a sync signal sent by a transducer being used to vibrate a particular part of an airframe.

The mid-air breakup of two passenger liners in the 1950s brought metal fatigue to the forefront of airframe design, and Solartron were there to supply designers with the test instruments the improved technology needed.

1 2 next

Moderator(s): Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Dave Billington, Bjørn, Steve Conner, Wolfram, Kizmo, Mads Barnkob