X-Authentication-Warning:	delorie.com: mail set sender to geda-user-bounces using -f
X-Recipient:	geda-user AT delorie DOT com
Subject:	Re: [geda-user] Stepper Driver Question
To:	geda-user AT delorie DOT com
References:	<CALSZ9grFdpWEWyU2LFhoDfSYCmXatFohBFyxNGfXdS-SnZ7pBw AT mail DOT gmail DOT com>
	<56BE4EF3 DOT 4040209 AT plastitar DOT com>
	<201602122147 DOT u1CLlmqo014914 AT envy DOT delorie DOT com>
From:	"P. Taylor" <phil AT plastitar DOT com>
Message-ID:	<56BE5664.2000407@plastitar.com>
Date:	Fri, 12 Feb 2016 17:02:12 -0500
User-Agent:	Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101
	Thunderbird/38.5.1
MIME-Version:	1.0
In-Reply-To:	<201602122147.u1CLlmqo014914@envy.delorie.com>
X-AntiAbuse:	This header was added to track abuse, please include it with any abuse report
X-AntiAbuse:	Primary Hostname - omega.hrwebservices.net
X-AntiAbuse:	Original Domain - delorie.com
X-AntiAbuse:	Originator/Caller UID/GID - [47 12] / [47 12]
X-AntiAbuse:	Sender Address Domain - plastitar.com
X-Get-Message-Sender-Via:	omega.hrwebservices.net: authenticated_id: phil AT plastitar DOT com
X-Authenticated-Sender:	omega.hrwebservices.net: phil AT plastitar DOT com
X-Source:
X-Source-Args:
X-Source-Dir:
Reply-To:	geda-user AT delorie DOT com
Errors-To:	nobody AT delorie DOT com
X-Mailing-List:	geda-user AT delorie DOT com
X-Unsubscribes-To:	listserv AT delorie DOT com

On 2/12/2016 4:47 PM, DJ Delorie wrote:
>> The drive for that chip is out of the audio range.
> The trace he posted says 10KHz, that's within *my* hearing range.  The
> question is, is there something that's turning that into mechanical
> noise?  Are there other variances in the PWM signal that might be
> audible?

The PWM is in the 60k range.

He is stepping the motor at 10k.

That might be the problem.

It is probably also why there is some timing glitch around 3k.

Just my two cents.

Phil

- Raw text -