<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div>Almost everything had a Master Item number, but some things that were accessories or sub modules seem to have had only a master item number with a verbal description of it such as an MI-nnnn bridging pad, etc. I'm not an RCA guy, but I have spent a few decades using, repairing, and studying RCA equipment and I've had some interesting conversations with RCA guys over the years. One observation I have is that, internally, RCA was not as monolithic as it might seem from the outside. The various RCA 'divisions' seem to have some degree of autonomy when it came to things like assigning model numbers. One evidence of this the graphical style of manuals and name tags, etc. The type faces used, kerning, layouts, etc., vary quite a bit from product to product, especially when you cross manufacturing lines from one product field to another, consumer to broadcast, or broadcast to communications, or radar, and so on. Some things are attributed to the RCA Manufacturing Company, some to RCA Victor Corporation, some to RCA inc., and so on. They use different type styles for the company name even for products made and sold at the same time. There doesn't seem to have been an overall image czar such as you might expect today. You can get a flavor of this by perusing the RCA equipment catalogues at <a href="http://AmericanRadioHistory.com">AmericanRadioHistory.com</a>. The 1939 catalog has an article that touches on the various internal divisions, for example. </div><div><br></div><div>Bob Bruner </div><div>WTTW retired<br>Sent from my iPad</div><div><br>On Oct 1, 2014, at 11:10 AM, <a href="mailto:Chill315@aol.com">Chill315@aol.com</a> wrote:<br><br></div><blockquote type="cite"><div>
<meta content="text/html; charset=US-ASCII" http-equiv="Content-Type">
<meta name="GENERATOR" content="MSHTML 8.00.6001.23588">
<font id="role_document" color="#000000" size="2" face="Arial">
<div>To pick up on the two previous emails.</div>
<div> </div>
<div>I just realized that the model numbers of RCA mics started with the
numbers, like in 77DX and 44BX while cameras started with the letters like
TK-41.<br>
<div apple-content-edited="true">
<div style="LINE-HEIGHT: normal; WIDOWS: 2; TEXT-TRANSFORM: none; FONT-VARIANT: normal; FONT-STYLE: normal; TEXT-INDENT: 0px; FONT-FAMILY: Helvetica; WORD-WRAP: break-word; WHITE-SPACE: normal; ORPHANS: 2; LETTER-SPACING: normal; COLOR: rgb(0,0,0); FONT-WEIGHT: normal; WORD-SPACING: 0px; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; -webkit-text-stroke-width: 0px"><span style="LINE-HEIGHT: normal; WIDOWS: 2; TEXT-TRANSFORM: none; FONT-VARIANT: normal; FONT-STYLE: normal; TEXT-INDENT: 0px; BORDER-SPACING: 0px; BORDER-COLLAPSE: separate; FONT-FAMILY: Helvetica; WHITE-SPACE: normal; ORPHANS: 2; LETTER-SPACING: normal; COLOR: rgb(0,0,0); FONT-WEIGHT: normal; WORD-SPACING: 0px; -webkit-text-stroke-width: 0px; -webkit-text-decorations-in-effect: none" class="Apple-style-span">
<div style="WORD-WRAP: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space"><span style="LINE-HEIGHT: normal; WIDOWS: 2; TEXT-TRANSFORM: none; FONT-VARIANT: normal; FONT-STYLE: normal; TEXT-INDENT: 0px; BORDER-SPACING: 0px; BORDER-COLLAPSE: separate; FONT-FAMILY: Helvetica; WHITE-SPACE: normal; ORPHANS: 2; LETTER-SPACING: normal; COLOR: rgb(0,0,0); FONT-WEIGHT: normal; WORD-SPACING: 0px; -webkit-text-stroke-width: 0px; -webkit-text-decorations-in-effect: none" class="Apple-style-span">
<div style="WORD-WRAP: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space"><span style="LINE-HEIGHT: normal; WIDOWS: 2; TEXT-TRANSFORM: none; FONT-VARIANT: normal; FONT-STYLE: normal; TEXT-INDENT: 0px; BORDER-SPACING: 0px; BORDER-COLLAPSE: separate; FONT-FAMILY: Helvetica; WHITE-SPACE: normal; ORPHANS: 2; LETTER-SPACING: normal; COLOR: rgb(0,0,0); FONT-WEIGHT: normal; WORD-SPACING: 0px; -webkit-text-stroke-width: 0px; -webkit-text-decorations-in-effect: none" class="Apple-style-span">
<div style="WORD-WRAP: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space"><span style="LINE-HEIGHT: normal; WIDOWS: 2; TEXT-TRANSFORM: none; FONT-VARIANT: normal; FONT-STYLE: normal; TEXT-INDENT: 0px; BORDER-SPACING: 0px; BORDER-COLLAPSE: separate; FONT-FAMILY: Helvetica; WHITE-SPACE: normal; ORPHANS: 2; LETTER-SPACING: normal; COLOR: rgb(0,0,0); FONT-WEIGHT: normal; WORD-SPACING: 0px; -webkit-text-stroke-width: 0px; -webkit-text-decorations-in-effect: none" class="Apple-style-span">
<div style="WORD-WRAP: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space"><span style="LINE-HEIGHT: normal; WIDOWS: 2; TEXT-TRANSFORM: none; FONT-VARIANT: normal; FONT-STYLE: normal; TEXT-INDENT: 0px; BORDER-SPACING: 0px; BORDER-COLLAPSE: separate; FONT-FAMILY: Helvetica; WHITE-SPACE: normal; ORPHANS: 2; LETTER-SPACING: normal; COLOR: rgb(0,0,0); FONT-WEIGHT: normal; WORD-SPACING: 0px; -webkit-text-stroke-width: 0px; -webkit-text-decorations-in-effect: none" class="Apple-style-span"><span style="WIDOWS: 2; TEXT-TRANSFORM: none; TEXT-INDENT: 0px; BORDER-SPACING: 0px; BORDER-COLLAPSE: separate; FONT: 12px Helvetica; WHITE-SPACE: normal; ORPHANS: 2; LETTER-SPACING: normal; COLOR: rgb(0,0,0); WORD-SPACING: 0px; -webkit-text-stroke-width: 0px; -webkit-text-decorations-in-effect: none" class="Apple-style-span">
<div style="WORD-WRAP: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space"><span style="WIDOWS: 2; TEXT-TRANSFORM: none; TEXT-INDENT: 0px; BORDER-SPACING: 0px; BORDER-COLLAPSE: separate; FONT: 12px Helvetica; WHITE-SPACE: normal; ORPHANS: 2; LETTER-SPACING: normal; COLOR: rgb(0,0,0); WORD-SPACING: 0px; -webkit-text-decorations-in-effect: none" class="Apple-style-span">
<div style="WORD-WRAP: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space"><span style="WIDOWS: 2; TEXT-TRANSFORM: none; TEXT-INDENT: 0px; BORDER-SPACING: 0px; BORDER-COLLAPSE: separate; FONT: 12px Helvetica; WHITE-SPACE: normal; ORPHANS: 2; LETTER-SPACING: normal; COLOR: rgb(0,0,0); WORD-SPACING: 0px; -webkit-text-decorations-in-effect: none" class="Apple-style-span">
<div>
<div><br class="Apple-interchange-newline">Best,</div>
<div>Park</div>
<div> </div><font size="2" face="Arial">
<div><font size="2">Park,</font><br>I think the distinction with RCA model numbers
is older gear vs newer -- <font size="2">Pre mid 1950s vs </font>post mid 1950s.
Earlier gear such as the iconic 76 consolette, or the 50D or 5D transmitters,
the 86 limiter, had numbers with postscript letters. For example my RCA
consolette is a 76B5. So most of the famous RCA microphones fall into this
group, the 44A<font size="2">,</font> B, BX, the 77A, B, C, D, DX, the 72 series,
etc. after the mid fifties, they went to a system with letter<font size="2">s</font> followed by a number, BC for consoles, B<font size="2">T</font>A
for AM transmitters, <font size="2">BTF for FM transmitters, </font>TT for TV
transmitters, SK for microphones, <font size="2">BA for broadcast audio devices
such as limiters, monitor amps, </font>etc. It's confusing because they didn't
change the model number on existing products, but continued to list them with
their original numbers side by side with the new lines using the new number
scheme.</div>
<div>Bob Bruner</div>
<div>WTTW retired <br></div>
<div> </div>
<div>It has always been a bit of a mystery to me how RCA decided on the model
numbers. </div>
<div> </div>
<div>T probably stood for Television. K for Camera. Possibly the
German version of the word? R for Recorder. S for switchers. G for
generators. M for monitors. P for projectors and film items.
</div>
<div> </div>
<div>So why some other names. WP for power? W something for other
items. TO for some scopes and WR for others. </div>
<div> </div>
<div>Many items just had an MI number which was the master index
number. </div>
<div> </div>
<div>So any help from a former RCA person that can explain the
nomenclature?</div>
<div> </div>
<div>Chris Hill</div>
<div>WA8IGN</div></font></div></span></div></span></div></span></span></div></span></div></span></div></span></div></span></div></div></div></font></div></blockquote></body></html>