Saying Goodbye To The Old RCA TT-11AH

Here's one last look at the TT-11AH.   Many of these pictures were taken about 10 minutes before the dismantling began.  The TT-11AH  served WDAZ as a backup transmitter from 1986 to January 2005.  Up until then, it  remained fully operational.  It  had to be removed to make room for the control racks of the new Harris Platinum Series HT25 transmitter.  Before coming to WDAZ,  the TT-11AH orginally belonged to KKTV in Colarado Springs.

The exciter and modulator

The control cabinet

The main power supply on the back wall of the transmitter

The Aural PA tube exposed

Behind the Power Amplifier section

Visual Modulator Amp 2KW Tube >>

<< 2KW 1st Aural Tube

1st Visual Tube >>

<< Aural Tripler Tube

Visual Tripler Tube >>

Inside the 2KW Cavity

Behind the 2KW amp section

If you hang around TV transmitters too long, you might turn a little weird.

Here's WDAZ engineer Mike and I with Jerry Servatius, next to the TT-11AH.  Jerry always came up in the autumn to put the main TT-25DH through a yearly proof of performance test.  If there was time left over, the backup would get some extra attention and a tune up.  Back when Jerry worked for RCA, he installed this very TT-11AH for KKTV.

Some Waveform Pictures From The TT-11's Last Checkup - 10/10/04

Differential Phase

Differential Gain

2T & 12T Pulses

Some of the evident hum and distortion is caused by interference from the main transmitter running at the time.

Horizontal Sync

Multiburst

RF Sweep

I have had many past and present television engineers tell me our TT-11 was the oldest operating TV transmitter they had ever seen. Upon hearing this, I thought I'd try finding a radio & TV museum to give it a new home. Most people told me they weren't interested or they didn't have space.  In the end it had to go.

Here I am taking apart a portion of the power supply

Mike just finished pulling off the control cabinet

Transmitter parts in the snow

Mike and I pushing/pulling out the PA cabinet

Sitting outside before being hauled away

The former home of the TT-11AH.  Take note of all the boxes on the other side of the corner windows.  That would be the new transmitter waiting to be assembled.  The left widow shows the RCA TT-25DH that will be used as a backup transmitter until the time we convert to digital HDTV in 2009.

A New Use For The Old TT-11AH Control Cabinet

During a week in October of 2007, while a painting crew was working up on the tower after sign-off, I needed a "small" project to keep me busy.  What I came up with was an odd computer case mod built from spare PC parts taking up space in my closet, and random junk found around the WDAZ transmitter building which hadn't been thrown out yet.  The most notorious piece of  "junk" used would be the control cabinet from the old TT-11AH.  The cabinet was stripped clean, but a few parts found new uses.  The indicator lights across the top were retro fitted with white LED's.  They're used as motherboard and hard drive indicator lights now.  After being lined with laminated wood, the low voltage regulator housing was used to mount the motherboard.  The breaker panel is used to turn on the power supply, monitor, keyboard illumination, and sound system.  The Overload Light Reset push button is now used as a computer reset switch, and the Plate Time Delay Bypass button is used for a motherboard power switch.  So all sides of the control cabinet could be enclosed, the end panel from the opposite side of the transmitter was saved, and so was a back door from a discarded RCA equipment rack.

The endmilled Computers iMonster

I'm still not sure what to do with it.  A pick-up truck would be needed to haul it away.  For now it sits in the control room processing BOINC projects.