Homebrew Drum Computer - test-drb@ccmp.vtda.org

15 Dec 2007

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Subject: Re: Homebrew Drum Computer
   From: ard at p850ug1.demon.co.uk (Tony Duell)
   Date: Sat, 15 Dec 2007 23:29:12 +0000 (GMT)
     To: cctalk at classiccmp.org

 I thought of this, too.  So far I haven't found an online source of  
 them (Google search terms: "glass delay line" OR "quartz delay line" 

 OR "ultrasonic delay line" TV PAL OR NTSC). 
I didn't think the NTSC system used a delay line at the receiver, but I 
must admit I've never repaired a US TV set. 
Yes they did/do but is was not ultrasonic.  The common ones were basically
the same as LONG (4.5us?) transmission lines.

They would be hard to find.

Allison

...
 It's not a common component for spares companies to
stock, simply because 
it rarely fails. And of course more modern TVs used IC delay lines, which 
are not what we want here.

When I wanted one, I went to an (alas long-gone) TV repair shop that also 
sold compoennts. No, they didn't keep them in stock, but the owner found 
a scrap PCB with a delay line on it. Needless to say that was acceptable.

-tony 