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  #31  
Old 10-17-2011, 09:53 AM
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I believe G! and cathode are reversed on the Predicta tubes. I will need to confirm that for sure. You can tie the heater winding to the 6 volt winding without trouble, or add a 6 volt filament transformer. If you have an old 110 tube brightner, remove the autotransformer, connect the filament windings to the filament transformer, reverse G1 and cathode (pending confirmation), install a tube like a 21CEP4 and you're good. This way, the modification is totally reversible if you find an exact replacement.
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  #32  
Old 10-17-2011, 09:24 PM
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I appreciate the tips guys - I'm not too concerned about the CRT length since the original neck guard is warped (from a wall heater I'd guess) and unusable - I'll have to fabricate a new one anyway. I plan on getting into the Miss America next year and will start a thread on her when I do.
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  #33  
Old 10-17-2011, 10:24 PM
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I suppose my favorite TV(s) will remain the 1948 thru 1951 RCA designed TV's based first upon the KCS28 chassis. This was the first major revamp after the chassis used in the 630TS and the KCS28 has many notable features:

1) Full bandwidth 4 MHz with 4 video IF stages AND with two upper adjacent channel traps, two lower adjacent channel traps, two video IF sound traps and one video amplifier trap. Certainly this was overkill but the traps provide the KCS28's excellent DXing capability.

2) First set to use the full Synchroguide Horizontal AFC circuit which predominated in many brands for the next decade.

3) DC coupled video amplifier. RCA persisted with DC coupling up until about 1952. Elimination of the video amplifier coupling capacitor yielded a better low frequency response and eliminated the need for a separate DC restorer tube.

4) Excellent sync peak AGC. The 630TS had no AGC because of the need to develop a circuit to develop a consistently accurate gain control voltage. I believe the KCS28 was a breakthrough in this regard with the sync tip amplitude reference circuit it used. (The final breakthrough was he "Keyed AGC" circuit developed in the next couple of years).

My RCA 8T243 was assembled in Montreal Canada. It was apparently the first TV manufactured in Canada in 1949, three years before the establishment of the first broadcast station there in September 1952 (CBLT Toronto and CBMT Montreal).

I have owned and maintained this receiver for 42 years as a regularly used set. In this time, I have aligned the set three times and replaced a number of tubes. Most of the paper capacitors have been replaced but a few have not shown any leakage and have left them in place. All the electrolytics are original. And the CRT is original to the set.

The images below include reception of WPBT Miami and KRMA Denver and Tu Canal Monterey Mexico from my rooftop antenna from Southern Illinois on this set.

These RCA sets are well designed and built like tanks.

Last edited by Penthode; 02-26-2025 at 08:42 PM.
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  #34  
Old 10-17-2011, 11:13 PM
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Kevin Kuehn Kevin Kuehn is offline
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Quote:
Originally Posted by Penthode View Post
The images below include reception of WPBT Miami and KRMA Denver and Tu Canal Monterey Mexico from my rooftop antenna from Southern Illinois on this set.
TV DXing- for real? That is just amazing.
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  #35  
Old 10-17-2011, 11:23 PM
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Just an average performer, but I'm very fond of my Blond 21-D-7177E RCA. Wish I could locate a NOS 21AMP4.
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  #36  
Old 10-18-2011, 12:31 AM
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Quote:
Originally Posted by Penthode View Post
I suppose my favorite TV(s) will remain the 1948 thru 1951 RCA designed TV's based first upon the KCS28 chassis.
I had no idea these sets were such an improvement over the 630TS chassis. That last picture especially is just stunningly clear. Your comments make me appreciate my (still unrestored) sets with this chassis much more.
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  #37  
Old 10-18-2011, 12:35 AM
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Regarding my favorite set(s) from the ones I own, it is a tough question. It might be the National NC-TV7, or the Zenith G2958R, or the RCA CT-100.
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  #38  
Old 10-18-2011, 04:08 AM
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It's a tie between my Predicta or my RCA projection set.




Click on image to see video







Click on image to see video

Last edited by Pielock373; 10-18-2011 at 04:25 AM.
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  #39  
Old 10-18-2011, 06:29 PM
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Quote:
Originally Posted by Kevin Kuehn View Post
TV DXing- for real? That is just amazing.
I forgot the KRMA channel 6 photo attachment. This reception was in late June 2009 after most of the analog TV stations had shut down. The few remaining VHF analog channels were just showing looped presentations.

Note the WPBT channel 2 was about 1000 miles, KRMA channel 6 was about 900 miles and channel 2 Monterrey Mexico about 1200 miles. And these were received directly by the original KRK5 RCA tuner in the set.

Last edited by Penthode; 05-18-2026 at 09:22 AM.
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  #40  
Old 10-18-2011, 08:41 PM
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I'm more of a solid state guy..it's what I 'cut my teeth' on...I didn't evn dig into a tube set until later on.

SO, that being said, i'm going on a limb here and saying it's my 1976 XAM 13" color metal cabinet tv...here it is listening to first responders on UHF 14...great pic, Toshiba Blackstripe 1 crt
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  #41  
Old 10-18-2011, 09:40 PM
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I remember the tales of my Admiral 1911A11...The guy who owned it would haul it up on this local Hill in summmer '48-49, & they would TRY to DX Atlanta (WSB or WAGA or Charlotte...WBT... An' They would stand up & HOLLER when they got a signal...Big Stuff in '48=49....(grin)
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  #42  
Old 10-18-2011, 09:48 PM
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Goin' To Noxfull Thursday...Hope to see Terry, & maybe get some of my Stuff back...Wish I knew how to work the Blonder-Tongue Agile Modulatotor to get a signal on all my TeeVees...
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  #43  
Old 10-18-2011, 10:26 PM
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Quote:
Originally Posted by Sandy G View Post
Wish I knew how to work the Blonder-Tongue Agile Modulatotor to get a signal on all my TeeVees...
This article explains how I hooked up my AM60-550A:

http://antiqueradio.org/HomeTVTransmitter.htm

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  #44  
Old 10-19-2011, 12:10 PM
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Sandy, that tale adout the admiral is very amusing. I assume there were no local stations in that area back then as who would go to the trouble to haul that thing up a hill and set up a power suply if there was an easier way to get a station. If that area was a TV signal "dead zone" though why would they pay for a TV to watch static on?
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  #45  
Old 10-19-2011, 02:23 PM
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Quote:
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why would they pay for a TV to watch static on?
I've paid for TV's that I haven't even plugged in...quite a few actually .
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