Accufork & pitch reliability - was Acufork II you want to sell?

[terryb]

I hope I didn't open up a can of worms here. I talked to Paul Sanderson 
about my Accu-Fork II and he suggested that the problem was my RCT. I 
thought he might have been correct at I checked it with Eugenia Carter's 
SAT III which said it was right on.  The battery was a new Duracell and 
both the unit and the battery were at room temperature. I ended up using 
the Reyburn Cyberfork for my exam. It was calibrated to be 0.09 cents sharp 
and my A4 ended up at 0.2 cents sharp.

Apparently Dean Reyburn doesn't recommend using the Cyberfork for the exam 
as it has a prominent second partial. I didn't notice it though.

Terry Beckingham

At 05:05 PM 7/1/2007 -0600, you wrote:
>Hi,
>Only thinkin
>Battery how old? Temperature make a difference with the battery?
>Best to use a new battery and recal before test.
>Joe Goss RPT
>Mother Goose Tools
><mailto:imatunr at srvinet.com>imatunr at srvinet.com
>www.mothergoosetools.com
>----- Original Message -----
>From: <mailto:formsma at gmail.com>John Formsma
>To: <mailto:pianotech at ptg.org>Pianotech List
>Sent: Sunday, July 01, 2007 4:44 PM
>Subject: Accufork & pitch reliability - was Acufork II you want to sell?
>
>I'm glad someone else brought this up. I think my AccuFork II also has 
>some pitch problems.
>Measurement a couple weeks ago with a friend's RCT showed variation of 0.4 
>cents, measured about five times in about couple minutes. I was taking the 
>RPT tuning exam at Kansas City, and the day before the exam calibrated the 
>AccuFork with the CTE's SAT III.
>
>The next day at the exam, the A4 I had tuned was 1.7 cents sharp. I had 
>checked with both B1 and F2, and was almost completely certain the beats 
>were the same as with the AccuFork.
>
>After the pitch part of the exam was over, I again checked the AccuFork 
>with the same SAT. It was about 0.4 - 0.6 cents sharp, judging from the 
>speed the lights were moving.  We didn't take time to calibrate the 
>AccuFork then; only to move the slider to the place where it was actually 
>A440 as measured by the SAT.
>
>Now, I passed the tuning exam with very high scores, so it was verified 
>that I can hear beats quite well. The only thing I can think of is that 
>the AccuFork pitch drifts, or I just didn't set the A4 pin and string 
>correctly (not very likely).
>
>I don't have an ETD, so it's kind of hard to visually check the AccuFork. 
>Last night, I downloaded a guitar tuner program to my Palm. It showed 
>about the same pitch variation as the RCT.
>
>What device should I trust more? The Palm? Or the AccuFork?
>
>Is there somewhere on the internet that is a totally reliable place to get 
>smack-on A440.00 Hz?  I'd like to figure out the problem, but don't really 
>know which device to begin with. I suppose I could download a trial 
>version of TuneLab, but how would I know it is more precise than the 
>AccuFork? (Do ETDs drift too?)
>
>Yes, yes, I know I'm talking about 0.4 cents at most, so it's not that big 
>of a deal. But I would like to have it within 0.1 cents, if not dead on.
>
>JF

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