Sorry — just seeing this now. 

Usual speeds were between 32-38 Rpm. I’ll usually key it off any AC line hum there might be. 

There is no technical difference between red and blue belts, simply when they were made. Red belts were made until 1964. Blue belts from 1964-1975. There were also purple belts until 1980. 

Hope this helps. 
Jeff


On Wed, 3 Jul 2019 07:28:47 -0700, Shai Drori <[log in to unmask]> wrote:

>Hi Jeff
>Thank you for the information. I heard of the slow speed ones but never had
>one to transfer. I get the usual 20 minute variety. Do you know the
>original mandrel speed or the linear speed of the belts. And one last
>question was there a difference between the blue and red belts?
>
>On Wed, 3 Jul 2019 at 5:26 Jeff Willens <[log in to unmask]> wrote:
>
>> Hi Shai,
>>
>> You can use a standard microgroove stylus without a problem. Dictabelts
>> are pretty resilient. I would start there and see where you need to go.
>>
>> Do keep in mind though that the standard speeds could range from 32-38
>> RPM. South African belts even ran at 19 RPM for longer playing times.
>>
>> Jeff
>>
>>
>>
>>
>>
>> On Tue, 2 Jul 2019 12:36:04 +0300, Shai Drori <[log in to unmask]> wrote:
>>
>> >Does anyone know what size stylus would be good to track dictabelts?
>> >
>> >Cheers
>> >Shai Drori
>> >Expert digitization services for Audio Video
>> >3K scanning for film 8mm-35mm
>> >Timeless Recordings Music Label
>> >www.audiovideofilm.com
>> >[log in to unmask]
>> >Tripadvisor level 6 contributor, level 15 restaurant expert
>>
>--
>
>Cheers
>Shai Drori
>Expert digitization services for Audio Video
>3K scanning for film 8mm-35mm
>Timeless Recordings Music Label
>www.audiovideofilm.com
>[log in to unmask]
>Tripadvisor level 6 contributor, level 15 restaurant expert