<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>On Dec 20, 2008, at 5:57 PM, Don Norwood wrote:</div><div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><div bgcolor="#ffffff" style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>Hi Ted:</div><div> </div><div>According to my RCA catalog, this part number is a 5-mil headwheel with ball bearings. </div></div></span></blockquote><div><br></div><div>So this would likely have been used to record tapes at 7.5 ips? </div><div><br></div><div>What machines did it fit?</div><div><br></div><br><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><div bgcolor="#ffffff" style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>A bit of headwheel trivia.......These lowband headwheels were offered with either ball bearings or air bearings. I believe that RCA was the first to offer air bearings, while Ampex was the first to offer rotary transformers. RCA apparently continued to offer the lowband heads after they developed their highband head. However, after Ampex introduced the Mark Ten for highband, they no longer made their lowband panels, but versions of the Mark Ten were available for low band. As far as I know, there were never any of the Ampex lowband Mark Three panels that had air bearings, but the Mark Ten was available either way to accomodate machines without the air package.</div><div> </div><div>Don</div></div></span></blockquote><div><br></div><div><br></div><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><div bgcolor="#ffffff" style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><blockquote style="padding-right: 0px; padding-left: 5px; margin-left: 5px; border-left-color: rgb(0, 0, 0); border-left-width: 2px; border-left-style: solid; margin-right: 0px; "><div style="font: normal normal normal 10pt/normal arial; ">----- Original Message -----</div><div style="background-image: initial; background-repeat: initial; background-attachment: initial; -webkit-background-clip: initial; -webkit-background-origin: initial; background-color: rgb(228, 228, 228); font: normal normal normal 10pt/normal arial; background-position: initial initial; "><b>From:</b><span class="Apple-converted-space"> </span><a title="ted@tedlangdell.com" href="mailto:ted@tedlangdell.com">Ted Langdell</a></div><div style="font: normal normal normal 10pt/normal arial; "><b>To:</b><span class="Apple-converted-space"> </span><a title="quadlist@quadvideotapegroup.com" href="mailto:quadlist@quadvideotapegroup.com">Quad List</a></div><div style="font: normal normal normal 10pt/normal arial; "><b>Sent:</b><span class="Apple-converted-space"> </span>Friday, December 19, 2008 10:14 PM</div><div style="font: normal normal normal 10pt/normal arial; "><b>Subject:</b><span class="Apple-converted-space"> </span>[QuadList] RCA TRT Quad Headwheel panel on ebay</div><div><br></div><div>This has apparently been on ebay for a while. </div><div><br></div><div>RCA part MI-40791-AZ, serial 3203.</div><div><br></div><div><font class="Apple-style-span" color="#144fae"><span class="Apple-style-span" style="text-decoration: underline; "><a href="http://cgi.ebay.com/Vintage-Quadruplex-VTR-Headwheel-RCA-TRT-Quad_W0QQitemZ230252354142QQcmdZViewItemQQptZVideo_recorders_Players?hash=item230252354142&_trksid=p3286.c0.m14&_trkparms=66%253A4%257C65%253A1%257C39%253A1%257C240%253A1318#ebayphotohosting">http://cgi.ebay.com/Vintage-Quadruplex-VTR-Headwheel-RCA-TRT-Quad_W0QQitemZ230252354142QQcmdZViewItemQQptZVideo_recorders_Players?hash=item230252354142&_trksid=p3286.c0.m14&_trkparms=66%253A4%257C65%253A1%257C39%253A1%257C240%253A1318#ebayphotohosting</a></span></font></div><div><br></div><div>Hope everyone is warm and dry... and doesn't suffer a power outage or air loss while the headwheel is spinning. </div><div><br></div><div>Ted</div></blockquote></div></span></blockquote></div></body></html>