Align your space command remote chassis with ease!
 

I have been keeping my eye open for a simpson 407 remote aligner for years on ebay. Never seen one show up. I figured it was the only tool to use to properly align the detector coils on a space command remote chassis. If you ever replace the caps which normally go bad, you need to touch up the coils. Ive used the actual clicker to try to find the most resonant spot on the coils. It works, but its not good enough for maximum sensitivity alignment. It occured to me that I might be able to modify an ultrasonic electronic remote to match the freqs of the original space command remotes. I have a good number of space command manuals and looked at one for the space command 1000 to find out what the factory freqs were supposed to be. I have SP-24 which covers the F line for 1975. To my amazement, there was a section on the very back of the manual explaining how to modify a space command 1000 remote to match the freqs of the mechanical remote for alignment purposes. It was also noted that the the simpson remote aligner was "NO LONGER AVAILABLE", so thats been obsolete since at lease '75. That would explain why they are so hard to find.
But, this modification works perfectly and quite simple. this is only explained in the 1975 space command manual. Later volumes show how to align the remote, but not alter it for older models. One or more of these four fundamental frequencies are on ALL mechanical space command remotes unless it has the blue button in place of the orange button on the newer remotes which means it uses different frequency (40.74 kHz), which was not introduced until 1976.

The modification required only 7 resistors, which are unique values so you might have to special order them. The space command 1000 remotes are a dime a dozen, so it was no problem getting a spare remote to modify. It calls for 16, 24, 200, and 1K , 1/4W 5% resistors as shown in the schematic. I used 2% in this case for more stability. You are to replace the SIP resistor and replace with these. Fortunately, zenith already had the resistors locations ready to go on the PC board including the numbers. It was simply remove the sip, install the new resistors and align the coil and the trimmer for the highest and lowest freqs. the rest of the freqs fell into place. Looking at the 3rd photo, the remote in front is the modified one, while the one above it is original with the sip resistor which can be seen as R13. It is also necessary to label the remote with the changed freqs. Also to note, the new freqs do not match the function of those originally labeled on the face of the remote.


Once you have this made, all you need to do is find the transistor in the detector circuit of the frequency that needs adjustment and clip your negative meter lead to it and positive to gound. Set your meter to 50 VDC scale. Hit the remote and align for minimum voltage peak. Its that simple and the remote works perfect after that. You will be rewarded with a remote chassis that is sensitive and responds from extreme distances from the set. Not that thats so important, but its especially important if you like to skip channels. By having the chassis aligned properly, the relay should stay closed with the remote button held down for a couple seconds thus skiping channels. Also helpful for adjusting the tint if you have a space command 600.

I was surprized how much better you can get the remote to work, even if its working ok as it is. Build one of these and keep your space commanders in top notch shape!

Very cool Doug, I'd like to make one of those too!

000

I bought a Space Command 400 remote from that ePay place:
http://cgi.ebay.com/ws/eBayISAPI.dll...m=330223873934

Completely mechanical, pressing each spring-loaded button causes a striker to ping a corresponding tuning fork.

I struck each button into the mike of an audio spectrum analyzer. Results were as follows:

Channel-Higher button:
http://www.audiokarma.org/forums/att...9&d=1208295903

Channel-Lower button
http://www.audiokarma.org/forums/att...0&d=1208295903

Sound/Mute button
http://www.audiokarma.org/forums/att...1&d=1208295903

Volume-On/Off button
http://www.audiokarma.org/forums/att...2&d=1208295903

Channel-higher ping -- 9.04 KHz.
Channel-lower ping -- 8.33 kHz
Sound/Mute ping -- 8.07 kHz
Volume-On/Off ping -- 7.66 kHz.

(Measurements taken at curve peak).

There's a pretty good (but not great) correspondence between 5X these values and your values. Obviously your remote is truly "ultrasonic". Mine is quite audible. I remember urban legends that dogs used to be able to change channels on these TVs by barking. Maybe that's why they upped the frequency (when electronics advances made it possible).

I wonder what the "spec" frequencies are for the 400. Does my remote need tuned? How do you tune a mechanical version?

Related fun here: http://www.audiokarma.org/forums/sho...39#post1792639

Cool, now I just need a Space Command Zenith! :yes:

Barking? Heck, on the Panasonic set with (electronic) ultrasonic remote that my parents used to have, you could change the channels / adjust volume / switch the set on and off by jingling keys on a keyring, or tossing a handful of loose change, or rattling a metal-link watchband. Or any number of other sounds for that matter. My brother and I would intentionally disrupt whatever show the other one was watching by making sounds like that. With practice, you could actually learn the "technique" that was most likely to get the TV to perform the particular function you wanted.

It could really drive you batty at times, since random sounds around the house would sometimes trigger the TV remote system. I seem to recall that at least one time we were on vacation, and when we came back, we found the TV had switched itself on while we were gone.

Now, during the same time period, we also had a Zenith with "Computer Space Command" ultrasonic remote, but the Zenith was almost impossible to fool with stuff like that. Actually, even the old Zenith mechanical ultrasonic remote systems seem to be well designed from that standpoint.

I've heard those stories about keys, change, etc. Tried them on my space commands and never got one blip of false activity.

Might work on a lesser set, but the the Zenith Space Commanders are the only remote sets to survive in any number circa 2008!

Would be a good mythbusters!

Actually, those use tuned metal rods, much like tuning forks. You can tuna fish, but you can't tune a fork.

My Dad got freaked out by the first color set I ever fixed. It was an early 19" solid state color Zenith with the four-button clicker remote. I had it set up in his basement woodworking shop. One day while I was at school, he turned on one of his saws and it turned the TV on! He said he looked all over the shop to make sure someone wasn't there to turn the TV on. When I got home, I had to explain to him how it happened.

I had a 4-tube SC (drh now has it) that I had loaned to my grandfather's live-in housekeeper. One night while watching the set something got stuck and it wouldn't quite switching channels. Same thing happened on my old late 50s Space Command. I took the cheaters way out and just turned off the master remote switch.

Zeniths are hard to trick. With a large key chain full of keys, you can sometimes get the set to function, but you need to vigorously shake the keys and be within a few feet of the set. Obviously, key shapes are the big issue here.

The only time Ive actually had a true false trigger was with the telephone bell. I have a western electric 500 in the basement. If I turn the sensitivity all the way up on a space command and keep the loud-soft on the phone at loud, the set will turn on if the phone rings. There were a few instances where Id come home and hear the TV going. I couldnt quite figure it out until the phone rang and the big relay clicked on in the TV! After 4 phone rings, the set would shut back off, which was perfect as the phone only rings 4 times before voice mail answers.

My only conclusion to the TV staying on was someone hung up before the VM answered.

It was possible to trigger the old mechanical SC remotes with stray sounds from jingling keys and the like. One of my favorite stories about remote false triggering had to do with a set that would switch on and off, change channels, etc., at random, whenever the owner's dog was in the living room. The problem was that the metal tags on the dog's collar would clink against each other or the collar, creating an ultrasonic signal of just the right frequency to activate one of the remote functions. Another remote control system which had problems like that, only much worse as I will explain, was Zenith's Flash-Matic remote from the mid-1950s. This was the company's first attempt at wireless remote control; the gizmo worked, but it had problems. The worst of these was that, if stray light of any kind would strike the photocells located at each corner of the CRT mask, all heck would break loose. No kidding; the sound would switch on and off, the TV itself would switch on and off at random intervals (sometimes in the middle of the night), the volume would rise and fall, the tuner would switch channels at random . . . I'm sure it was a mess times at least ten. This remote system had such problems because there were no lockout schemes to keep from activating more than one function at a time with the remote's own light beam, or to prevent or minimize false triggering from external light hitting the photocells. I have often wondered how many of these sets were damaged by the tuner trying to rotate in two directions at once (burning out the tuning motor and/or stripping the drive gears), when sunlight hit both channel-change photocells simultaneously. The same thing could happen with the volume control if both photocells were illuminated at the same time. I think this problem, combined with the fact that no one could remember which cell did what, was Flashmatic's eventual undoing; the system was discontinued after only one model year, being replaced by ultrasonic remote control in the late '50s-sixties.....and as it has been said, the rest is history.

I suspect your spectrum analyzer does not go up to ultrasonic frequencies? The spectrum content you recorded could be the damped "tink" you hear on the mechanical remotes - and/or either a subharmonic or distortion in your microphone. I believe the actual frequency in use would be higher and purer [edit: - and louder - much too loud and annoying if it really worked at those lower frequencies] , but I'm just guessing. At one time I built a mixer to convert the ultrasonic down to audible frequencies - it was interesting to hear what produced loud ultrasonic vibrations.

I had a 75 Heathkit with ultrasonic remote. The dog could turn it on and off, which I discovered when I came home to find it on. However, it wasn't his collar or tags or the remote at all - just his big tail hitting the big on/off buttons on the front.

oldtvnut is correct. Your spectrum analyzer is picking up a sub harmonic of the ultrasonic frequency since it doesnt repond to the ultrasonic freqs. The true frequency of the space command 400, which is the same as the 600:

37.75 kHz, volume stepper/on-off

38.75 kHz, mute

40.25 kHz, channel lower

41.25 kHz, channel higher

This modified 1000 remote control will enable you to align the receiver of all sets that use the mechanical remotes, since its an electronic oscillator and transmits a constant frequency of constant amplitude as long as the button is pressed, making alignment quick and simple.