RCA Remote Control
 

I have 2 hand units for a CTC-16 or 15. One is in very bad shape but both have the same curious issue. They are both way off frequency.

The native frequency of the Tint Up (using the coil only) is way off and so the others also.

The generated signal is very strong and any connection to measure it affects the frequency. The suggested method is to use a loosely coupled probe (just lay it close) and zero beat it with another known good remote or a known frequency standard. This zero beat is the way to go because there is no loading.

What I have discovered is the frequency is reasonably stable over a range of battery volts and handling.
The frequency is only about 25 kc at best but is adjustable.

My question is, the Sam's says 35 khz should be the native freq before the adjustable caps are switched in for the other functions (higher frequencies). In my mind I would expect these would lower the freq not raise it like the alignment chart shows.

Is my information bad? Does the RCA factory information say something different? Anyone have experience with these?

Back in the day the only thing we did was replace the battery and touch up the alignment of the recievers. Never exposed to anything exibiting a drastic problem with these things.

Kinda shocking that no one here is helping.. Or at least any kind of input..

I'll chime in - we used an ultrasonic mic (transducer robbed from another remote), a simple audio amp, and a frequency counter (robbed from the tape deck bench) to check clickers. I've seen folks use a Fluke 179 meter to check them too - albeit not an RCA unit, but a Magnavox. The 179 does frequency to 50Khz, and measures with a high-input impedance, so no loading, as some 50 ohm/1M ohm frequency counters do. You can also sometimes measure the clicker frequency by using the remote receiver

Leakage in the transistor can cause a frequency shift - a 2N406 is called for in most of the RCAs, but you can use just about any germanium audio transistor to replace it.

Oh, and make sure you have the right CRK ! They do have different frequencies - the 5A and 6A are almost identical, the battery (and battery voltage) being a significant difference. The higher-numbered units ( 7, 9, and up) are w-a-a-y different in freqs.

Hope this helps!

Cheers,

I've got NOS germaniun on hand and will give it a try
Tyhese are both 5s. The battery for one is VS-328 and the other is VS-163 4.5v. The Sam's says 9volt! It has to be wrong. If I power it w/ 9v the transducer will arc!
Im suspecting there was (back in the day) a handy service replacement available if these went belly up or the slide contacts broke or corroded.
Sounds like good insight, THANKS Maybe well get more.

Still sooooo off
 

Transistor replaced, but still way off. Core adjusts from 14khz to 25khz.
Voltage makes only a slight difference, handling makes only a very slight difference. Measuring using loose coupled with a scope and generator to zero-beat or loose sampled with a freq counter results are the same.
I'm begining to feel strongly that the Sams info is not correct. Hope there is someone with RCA factory info that will prove one way or the other.
This device seems to "want" to work in this range no matter what I try with it.
I know crystal microphones deteriorate with age and humidity, could this transducer be doing likwise? It is in paralell with the tuning method.

Checked all solder joints? Are there any caps to dry out in the thing? Resistors to drift?

Any chance the receivers are tuned to the second harmonic of the transmitter? If so 17.5kc would be right in the ball park of your range. My RCA field service manual only specifies the 35-44kc tuning of the receiver, nothing on the transmitters.

Here's the schematic for the CRK5A from the RCA field Service manual. They don't call out native osc frequency, but take note of the frequencies next to the remote function switches. Somehow I missed those the first time I looked at it. Also, on the CTC-9-11(CRK3A-B,) they call out 19.125kc as the native oscillator frequency. CRK3A-B Looks like the same basic circuit using the 2N406.

http://i452.photobucket.com/albums/q...ps26605a37.jpg

That might make sense. The freqa listed on the various function are in my ballpark. I havea spare recieveravailable and imay usethat to test that with. This maybe the solid lead i'v been looking for..

Ps...I hate glass keybds on the run !

Thanks Kevin, your post had the info that made it all click. The handhend generates a signal at half what the reciever is tuned to. 22 kc is doubled at the reciever and tuned at 44 and so forth. I now have 2 working remotes for TVCOLLECTOR.
A loose coupled counter works fine. Now all we need is a 4 volt battery (or close) My make a sleeve for some calc / watch cells. Battery Plus here we come.

Glad to hear it worked out. :thmbsp:

Just installed a 3.6 v battery that fit the form factor and touched up the coil. It 'll be interesting to see how long it lasts before replacement is needed. When it gets close to 3v the freq varies by a big margin. The coil was zero'd in with the 3.6v and the rest were less than 5% out I suspect this is well within the pass band of the tunings for the functions. I've not had the TV to test with this time so a touch up may be in order anyway. TVCOLLECTOR is going to test it out.

Just installed a 3.6 v battery that fit the form factor and touched up the coil. It 'll be interesting to see how long it lasts before replacement is needed. When it gets close to 3v the freq varies by a big margin. The coil was zero'd in with the 3.6v and the rest were less than 5% out I suspect this is well within the pass band of the tunings for the functions. I've not had the TV to test with this time so a touch up may be in order anyway. TVCOLLECTOR is going to test it out.

My 58'RCA model7AH Grenoble which came with factory remote control
This hand unit is the size of a real small cigar box...LOL I've got the 2 chassis at Mr.Danny Sertich shop in Atlanta,Ga.
he's got the new power tranny working in the power supply up and running along with remote chassis,recapped,and tuning motor working,between me and him we should have a great working set some time this fall!! When I pay him for his time and trouble!!,
This set hasn't ran since the mid-70's when hit by lighting during a thunder clapp
I couldn't take the whole set down to just the 2 chassis he using a test CRT setup
To check out this Tv!
I'm going to use it everyday driver,the sets original Color CRT wasn't hurt by lighting and
Is in mint condition!!,wished I knew how to post pictures of this old roundie up and running this fall