Return-Path: Received: from [199.185.220.240] (HELO priv-edtnes57.telusplanet.net) by logan.com (CommuniGate Pro SMTP 4.1.1) with ESMTP id 2534100 for flyrotary@lancaironline.net; Tue, 19 Aug 2003 23:37:45 -0400 Received: from Endurance ([209.52.209.130]) by priv-edtnes57.telusplanet.net (InterMail vM.5.01.05.17 201-253-122-126-117-20021021) with SMTP id <20030820033742.FHQE27176.priv-edtnes57.telusplanet.net@Endurance> for ; Tue, 19 Aug 2003 21:37:42 -0600 From: "Haywire" To: "Rotary motors in aircraft" Subject: RE: [FlyRotary] Re: some progress, and more understanding Date: Tue, 19 Aug 2003 20:37:35 -0700 Message-ID: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0067_01C36691.B8BC11D0" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 This is a multi-part message in MIME format. ------=_NextPart_000_0067_01C36691.B8BC11D0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Hi Finn; It is a CMOS device capable of handling 20vdc on its VDD pin. So I didn't feel it was necessary. In reality I found it was unstable when VDD was less than 5vdc or greater than 11vdc, so since I had a bag of 470ohm resistors handy, I just put a voltage divider on the VDD. With a regulated 13.8vdc it gives me just under 7 volts and a stable reading. a side note; I originally had an internally regulated alternator but the regulator failed (have since converted to an external reg as per "electric Bob"). When running with the alternator tripped and less than 12vdc, I found the tach would become erratic at high RPM's, due to a low VDD. When alt is charging, everything is fine. S. Todd Bartrim Turbo 13B RV-9Endurance C-FSTB http://www3.telus.net/haywire/RV-9/C-FSTB.htm "Whatever you vividly imagine, Ardently desire, Sincerely believe in, Enthusiastically act upon, Must inevitably come to pass". -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]On Behalf Of Finn Lassen Sent: Tuesday, August 19, 2003 8:23 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: some progress, and more understanding I don't see a Zener diode to clamp any spikes. Finn Haywire wrote: Attached are a couple of pics of my tach divider. It can be set to divide by any number necessary. I can't guarantee it would work with any tach but it works very well with my cheap off-the-shelf-at-any-autoparts-store, Hastings tach. I have a few more if anybody wants one. S. Todd Bartrim Turbo 13B RV-9Endurance C-FSTB http://www3.telus.net/haywire/RV-9/C-FSTB.htm "Whatever you vividly imagine, Ardently desire, Sincerely believe in, Enthusiastically act upon, Must inevitably come to pass". The EC-2 tach output has 12 pulses per revolution, and won't directly work with any normal tach. Todd has made a divider to bring the pulse rate down to normal, and it sounds like it's working well. The TT that you have expects 1 pulse per rev, so if you don't mind dividing the rpm reading by 12... :-) ------=_NextPart_000_0067_01C36691.B8BC11D0 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Hi=20 Finn;

It is a CMOS device capable of handling 20vdc = on its VDD=20 pin. So I didn't feel it was necessary. In reality I found it was = unstable when=20 VDD was less than 5vdc or greater than 11vdc, so since I had a bag of = 470ohm=20 resistors handy, I just put a voltage divider on the VDD. With a = regulated=20 13.8vdc it gives me just under 7 volts and a stable reading.=20

a side note; I originally had an internally = regulated=20 alternator but the regulator failed (have since converted to an external = reg as=20 per "electric Bob"). When running with the alternator tripped and less = than=20 12vdc, I found the tach would become erratic at high RPM's, due to a low = VDD.=20 When alt is charging, everything is fine.

S. Todd Bartrim
Turbo 13B = RV-9Endurance
C-FSTB
http://www3.telus.net/haywire/RV-9/C-FSTB.htm

= =20 "Whatever you vividly imagine, Ardently desire, Sincerely believe in,=20 Enthusiastically act upon, Must inevitably come to pass".

-----Original Message-----
From: Rotary motors in = aircraft=20 [mailto:flyrotary@lancaironline.net]On Behalf Of Finn=20 Lassen
Sent: Tuesday, August 19, 2003 8:23 PM
To: = Rotary=20 motors in aircraft
Subject: [FlyRotary] Re: some progress, = and more=20 understanding

I don't see a Zener diode to clamp = any=20 spikes.

Finn

Haywire wrote:

Attached are a couple of pics of my tach = divider.=20 It can be set to divide by any number necessary. I can't guarantee = it would=20 work with any tach but it works very well with my cheap=20 off-the-shelf-at-any-autoparts-store, Hastings tach. I have a few = more if=20 anybody wants one.

S. Todd Bartrim
Turbo 13B = RV-9Endurance
C-FSTB
http://www3.telus.net/haywire/RV-9/C-FSTB.htm

= =20 "Whatever you vividly imagine, Ardently desire, Sincerely believe = in,=20 Enthusiastically act upon, Must inevitably come to pass". =

The EC-2 tach=20 output has 12 pulses per revolution, and won't directly work with = any=20 normal tach. Todd has made a divider to bring the pulse rate = down to=20 normal, and it sounds like it's working well. The TT that = you have=20 expects 1 pulse per rev, so if you don't mind dividing the rpm = reading by=20 12... :-)
=

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