Timing Edison DD phonographs

[fran604g]

Hi folks,

I guess I'm a little slow; I just noticed that Re-Creations have what appears to be a timing strobe pattern on the label. I had thought it was just a graphic pattern, and nothing else.

How many people realize this?

Fran

[VintageTechnologies]

Hi folks,

I guess I'm a little slow; I just noticed that Re-Creations have what appears to be a timing strobe pattern on the label. I had thought it was just a graphic pattern, and nothing else.

How many people realize this?

DSC01719 (Large).JPG

Fran

As best as I can determine, it is NOT a strobe pattern although it certainly does look like one. I (and probably a lot of others) have tried to sync it and never got anything valid from it. Think back to the day - what pulsed light source would have been available to dealers then, much less the public? Alternating current was not universal then, and Edison was THE DC guy. The Edison company issued a tuning record and tuning fork to set the correct speed.

[pughphonos]

Fran, VT is right; I've read that in many sources also (re. that pattern not being a strobe pattern).

What I ended up doing is buying off E-bay (for a whopping $15) one of those hand-held laser tachometers, and they work great! You just put a small piece of reflective tape on the side of the turntable, direct the laser point onto the turntable side, and the tachometer will show the RPM in its screen. I'm really, really obsessive about correct speeds, so the tachometer has been a real blessing. Counting turntable revolutions with a watch is prone to error and not easy--whereas the tachometer will give you a very quick decimal reading (e.g. 79.7, 80.3, etc.).

Ralph

[fran604g]

As best as I can determine, it is NOT a strobe pattern although it certainly does look like one. I (and probably a lot of others) have tried to sync it and never got anything valid from it. Think back to the day - what pulsed light source would have been available to dealers then, much less the public? Alternating current was not universal then, and Edison was THE DC guy. The Edison company issued a tuning record and tuning fork to set the correct speed.

Ah, too bad, I thought I was onto something!

I was wondering about the mains current frequency, also. I believe that George Westinghouse's Power Station at Niagara Falls was built in 1895.

My C-19 at maximum RPM's is still too slow using the pattern on the DD's at 60Hz, and I know the tempo of the records is too fast using the "full" setting of the speed control, I use it backed off just a little.

*EDITED*

Fran

[fran604g]

Fran, VT is right; I've read that in many sources also (re. that pattern not being a strobe pattern).

What I ended up doing is buying off E-bay (for a whopping $15) one of those hand-held laser tachometers, and they work great! You just put a small piece of reflective tape on the side of the turntable, direct the laser point onto the turntable side, and the tachometer will show the RPM in its screen. I'm really, really obsessive about correct speeds, so the tachometer has been a real blessing. Counting turntable revolutions with a watch is inaccurate to the point of being useless--whereas the tachometer will give you a decimal reading (e.g. 79.7, 80.3, etc.).

Ralph

That sounds interesting, thanks, Ralph.

I have several timing discs for my standard turntables, I wonder if anyone ever created one for 80 RPM's? I like using them.

Fran

[VintageTechnologies]

Fran, there are several free software programs online that can be downloaded to create strobe disks for any speed you desire. Search this website, this discussion has come up before.

[WDC]

As usual, I have to pop in, that strobe discs are nowadays really not the easiest thing to use. I have been using a laser tachometer, which also works fine with white paper strips. You can set the speed up to a 1/10 and quite precisely. I ordered these directly from China, takes 2-3 weeks and works just fine.

At less than $12 with shipping included it is true a no-brainer:

http://www.ebay.com/itm/161114545438

[FloridaClay]

I cast my vote for the laser tachs also. Cheap, very accurate, and super easy to use. Would never go back to a strobe disk for anything other than an historical decoration.

Clay

[Chuck]

An 80 rpm strobe disk is very easy to make.
Just draw out a little disc on a piece of paper
using a compass. Make it about the size of a diamond
disc record label.

Then, using an accurate protractor, mark off radial
lines every 4 degrees, all around the disc.

360 divided by 4 is 90, so there will end up being
90 marks. Use a pencil so you can erase it if you
make any mistakes.

When finished, enlarge the pinhole made by the compass
out to a snug diameter to fit the center post
on the turntable.

To use, view under neon or fluorescent light.
Incandescent filaments do not work so well for this
because they never completely go dark at the zero-
crossing of the A-C sine wave.

Just today, in another thread here I described in
full detail how to make the viewing lamp using
a neon bulb.

So, there you go, you can make the viewing lamp
and the 80 rpm disc.

Or....you can go out and buy one of them tachometer
gizmos and use it until the battery dies, then go get
another battery.

I was a draftsman for many years, so it's easier and
less costly (spell that zero dollars) for me to
draw up my own strobe discs.

About the markings on the Edison diamond disc
label, you could get some idea what speed would
strobe it if the angle from the center out to the
marks is known.

4 degrees is 80 rpm.
6 degrees is 120 rpm.
8 degrees is 160 rpm.

Those are the only ones I've made so far and use.

7200 divided by the total number of marks equals
the speed at which the pattern appears to stand still.
(For 60 cycle power)

There's more, much more....anybody still awake??
Haha.

Chuck

[phonojim]

Below are addresses for two sites which will give you access to three different free strobe making programs. I have used Strobo times and find it very easy to work with. Personally though I like the laser tach much better than strobes and lights. Strobes used to work under any fluorescent lamp, so there was no need for a separate neon lamp, but now with high frequency electronic ballasts ballasts you must use a dedicated lamp or work under a fluorescent that you know has a magnetic ballast. For my purposes, the tach is simply much easier to use.

Hope this helps,

Jim
http://www.78rpm.com/rescat/strobe_info.htm
http://www.christerhamp.se/phono./strobo.html