Rialto K minor problems

[Mr. Dust]

I recently purchased a Rialto K. For the most part, all I have had to do is clean it up a bit, but on a few of the tibia stops, I will find two notes next to each other that don't make any sound. I am reading some of the other posts on this forum and have found a lot of info. *I have been*cleaning*pins, which has cleaned up a lot of notes, but there seems to still be two notes that won't sound on some of the Tibia stops. * I do not know how to check voltages etc. I am also confused about any cleaning or testing I should do on the Tibia trays. it seems also that the percussion only work on a section of notes on each stop.</p>

Could be other problems too, but I am new to this organ.*</p>

[jimmywilliams]

Mr. Dust,</P>


OK first thing's first. If the two notes not sounding are on the tibia side - here's what you do...</P>


1. Only use a single 8' tibia stop (on thesolo it is called Tibia Major; on theaccomp it is called TIbia Minor)</P>


2. Try the same note on both manuals.</P>


3. If the note is not sounding on both manuals, you have a problem in the tone generator set. You can verify this by changing to the 4' tibia stop and see if the same keys an octave higher are also silent.</P>


Start there. Let us know if it is a TG problem or not. If so there are things to do. If not, there are other things to try but I don't want to get into those yet.</P>


The percussion/omega circuit only works on the solo manual tibia stops but not on the lowest solo octave 8' pitch (IIRC). It does not work at all on the accomp manual nor on any of the non-tibia voices on either manual. Verify that you are missing percussion on the top manual tibia notes as described above and we can take things from there.</P>


We can get this working again - well worth the effort. Is this the 1107 model (no piano stop) or the 1135 model (has the green piano stop and the multi-rank celeste black tab)?</P>


Keep us up to date. There are several others here who have either worked on these, own them, or both.</P>


- Jim</P>
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[Mr. Dust]

Yes, I have the 1107 model. *</p>

It is the exact same notes that are missing on both the Tibia major and minor, so it must be a TG problem. *As far as the*percussion goes, I only hear it on one*octave*per stop, and the weird thing is, even if I push the Omega*button, there is 1 note that I still hear it on.*</p>

Thanks for your reply,Dustin.*</p>

[jimmywilliams]

Dustin,</P>


These are 2 distinct problems. First, let's try to handle the missing tibia pitches. Using the 8' tibia stop only, let us know what the missing notes are (i.e. G#2). The octave pitches are referred to as 1, 2, 3, 4, and 5 for each octave(the higheroctavescan besounded using the lower-numbered tibia stops, 4', 2', 1', etc., but it doesn't sound like you have problems on those higher octaves). Before going any further, try the "dead" notes on the solo manual but this time fully engage any volume boost black stop tabs (they are called Solo FF or something to that effect). If the note comes back when the volume tabs are full on (even if it is sluggish or "fades in") this points to one problem - the 230-ohm emmiter resistor for that note on the TG board has drifted way out of spec. If engaging the volume tabs makes no difference, we probably have to look elsewhere.</P>


I don't know how familiar you are with the innards of the organ but you should know a few things. The tibia generators are located on the right side of the organ, looking at it from the back. There are 12 separate chasis, one for each note. There are several octave oscillators on each chasis for the particular note. Let us know what tht "TG" number is - these should be marked TG-3 but I want to be sure. These are connected by way of two wire harnesses (one for accomp, one for solo) to junction strips using two multi-pin jacks. If you have to remove the TGs, remove the 2 screws from the back, and then remove the front of the organ and carefully unplug the 2 harnesses for the appropriate TG from the junction strips. The sockets should be labeled with the note. You can then carefully pull the TG out from the back, taking care to make sure the wire harnesses do not get stuck and pull on anything else.</P>


Regarding the sustain circuit, I can't say for sure where the omega unit is on your organ. If it is like most, it will be mounted at the back of the solo keyswitch assembly. It will be a long board with 72 capacitors and diodes. Some early models had the omega unit located underneath the tibia junction strips at the front of the organ, however (one that I worked on was this old configuration). So, first find out where the omega unit is. Based on what you are saying, it will most likely need some work. But we can do that later. You can double-check to make sure all connections are tight and clean the connection points accordingly and see if that makes any difference. But, for now, try the test I mentioned above for the dead tibia notes and we'll take it from there.</P>


- jim</P>

[Mr. Dust]

The missing notes are D#3 and E3. I tried the solo switches and nothing. Although out of the blue, there was one time I turned it on and all the notes worked on the 8' tibia, that was weird. somtimes at full volume, I can hear a slight electrical connection, but no note. *I pulled the*corresponding*tone generators and I guess I will try cleaning the connections?*</p>

*</p>

-Dust*</p>

[jimmywilliams]

Dust,</P>


THat is strange that it did work intermittently; yeah try cleaning the connections (socket and pins) and see if that helps. Something may be loose or dirty. That would be great if that's the only issue. Be careful to put the harnesses back in the corect place; see where the short and long harnesses for the other TGs go (in the right junction strips) - they are not reversable. </P>


If this still doesn;t woirk...While you have the TGs out, you can measure the 230-ohm emitter resistor in circuit. The boards (the "back" board, not the board that the tuning coils are located) on those are labelled with each octave so it will be easy to identify the resistor wired to the emitter of the transistor for that octave (the transistor connnections are also marked on the board (C - collector, B - base, or E - emiitter). I've had them drift as high as over 1200 ohms! If they are significantly over230 ohms they should be replaced (I think they were rated at 10% tolerance). Also, I believe in octave 3 there are two 10uF electrolytic caps; they can be replaced as well - make sure you observe the correct parity as they are electrolytics.</P>


Of course, do a visual spot check for anything loose or disconnected; could save you some trouble. Keep us up to date.</P>


-jim</P>

[Mr. Dust]

Thanks for all your help, and sorry for the very long response time. I ended up finding another rialto that I could pic for parts. I just replaced the whole tone generators since I know nothing about reading a multi-meter or anything electronic for that matter. Everything sounds good now, except for the problem with the reverb. I'm also not quite sure if the chimes sound right, but I am really loving this organ! I am going to do some more cleaning on it, but let me know if you have any tips. Thanks again.</p>

Also I wanted to mention that a guy I know is trying to get rid of one of the later Rialtos, and he has the 102 and 103 speakers for it. he is only missing the pedal-board. I would buy it, but I am a little tight on cash for the next two weeks.*</p>

[Tinker]

That was great that you had another Rialto K to draw on for parts to help you isolate the problem. A quick swap of some of one tone generator for another within the same instrument would have also helped isolate it but your fix was even easier ;^) I fell in love with the sound and the touch of a Rialto K just like yours. I got it when a seller offered me a Rialto II and it turned out to be a Rialto K. A very pleasant surprise indeed. Mine had a number of problems (blown fuses, bad relay contacts and one relay coil, blown resistor in the 100GK amp) but it's been rock solid and a joy to play for the last year (knock on wood). As you're finding out, if the Rialto K sound appeals to you it's not long before you find out about the later models and start to wonder about how they sound. Looks like you've already got to that step. I found a nice 1135 with the ElectroMute and the Piano option along with a 102/103 pair. A bit more technically complex (in other words, more to go wrong) in both the console and Leslie's and to me a very different sound than the model you currently have. I've got the 102 and 103 on opposite sides of the area and they really create a rich and full sound. I think the piano is exceptional. I had hoped that I could compare both and make a decision as to which one to keep but for me it wasn't that easy. I still enjoy both of them, my original organ stayed in the garage for early morning and late night practice and the 1135 joined some others in the living room. If you get a chance to pick up the 1135, especially if it has the piano option I'd say do it. You'll no doubt have some tougher troubleshooting ahead of you but it's worth it. </p>

You may want to start looking for space for both of them... If you do pick it up let us know your impressions of the differences.</p>

I'll read back on the posts and see if I can add anything to the tips that Jimmy has already passed along. On the chimes remember that the piston i is going to activate a number of the Tibia pitches (which are selectable with console tabs) as well as a 6-2/5 Tibia "humtone" that's only used with the chimes (it can't be manually selected with a tab). If you need help identifying which of the switching solenoids should be activating, etc. just let us know. When they're working correctly I think they're fairly realistic.</p>

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