[BC] Cart machines

[RichardBJohnson at comcast.net]

I'm not sure any cartridge machine was any good by today's standards. There is far less wear and tear from reading a commercial or jingle off a disk drive than there ever was having NAB carts slammed into cart machines at the last instant because the DJ was caught asleep at the switch.

Often the machines that are most often used, because of price or availability, get the brunt of the abuse and complaints.

My bet is that it is IMPOSSIBLE to make a reliable cart machine because:

(1)	The "against physics" design of the cartridges where the tape is pulled out from the hub, forcing all the tape layers to slide over each other. Each layer of tape has a different rotational radius --defective in concept, impossible to properly design. 

(2)	The "against physics" design of hiding a pressure roller until the cartridge is in place, requiring that its axle rotate 90 degrees on a spindle, after which it must pull the tape evenly across the head without skew --defective in concept, impossible to properly design.

(3)	The "against physics" design requiring that the tape stop at the correct place, queued up, ready for instant replay. This is possible, but only if the tape is subjected to great friction resulting is great wear.

I know that Cetec/Sparta had a mechanical engineer (John Fernandez), trained to make man-rated rocket engines (read exceedingly reliable), who worked for Aerojet General for many years, design their version of the cartridge machine. He did not want to be involved because they could not be properly designed as the entire concept was wrong. Nevertheless, to complete the line of broadcast equipment Sparta designed just about everything that would operate in the studios as well as the transmitter sites.

So if you had the misfortune of maintaining cart machines, I'm sorry. They were all bad. Some tried to compensate by having many adjustments. This was okay if you had a screwdriver-mechanic standing by all daylong, others tried to compensate with heavy deck-plates and powerful solenoids. Nothing worked. Cart Machines; RIP.

Cheers,
Richard B. Johnson
Book: http://www.AbominableFirebug.com/

----- Original Message -----
From: "Dale H. Cook" <radiotest at plymouthcolony.net>

At 07:50 AM 11/23/2010, Cowboy wrote:

>>"worst cart machine"

>Anything and everything from Ampro ?

Those were bad enough, but I think Audicord was worse.