Tonewheel bleedthrough - is this normal?

[Guest]

Is it normal to have tonewheel bleedthrough in your output (the faint sound of all tones playing at once)? If so, how much is acceptable? On mine it's not too bad... at normal listening levelsit's slightly louder thanthe motor. But the odd thing is that it changes volume over time. It seems to get louder when nothing is being played, but as soon as you hit a note it gets quiet again. Then it slowly builds up.</P>


And here's another noob question. Can someone suggest where to find Hammond generator oil? There are so people on ebay claiming to sell the "real thing", but ...you know how ebay is... I'd feel more comfortable if someone could refer me to a reputable vendor.</P>


Thanks</P>

[geoelectro]

Re: Tonewheel bleedthrough - is this normal?



Ground check time. Looking at the generator from the rear of the organ, on the bass end, you will see where the generator cable from the pedals and manuals connect to the solder lugs on the generator terminal strip. The last wires are grounds. This is the main ground point of the organ. Just below the ground terminals, a bare wire goes into a lug with a screw into the generator. Tighten that screw. Secondly, one of the ground wires goes up to the bottom of the preset panel. On the right end, tighten the screw with the black wires. Look to the middle of the panel and tighten both screws where the upper and lower panels are jumpered.</p>

See if that helps.</p>

George
</p>

[Guest]

Re: Tonewheel bleedthrough - is this normal?



George, you're my hero!! Oh how nice it is when a problem can be solved with a quarter turn of a screwdriver. Bleedthrough completely GONE [&lt;:o)]</P>


Speaking of grounding, is it a good idea to modify the organ with a 3-prong power plug (for safety as well as noise reduction)? And if so, is this the spot where I should wire the ground conductor?</P>

[Guest]

Re: Tonewheel bleedthrough - is this normal?

i have a this bleedthrough problem on my l112 sometimes, but it's very faint, and is rarely very audible

[andyg]

Re: Tonewheel bleedthrough - is this normal?

I've never had a Hammond that didn't feature this. In fact the clones and software Hammonds are quick to point out that they put it back in to make things more realistic! It shouldn't be too noticeable, though!

[johnny b3]

Re: Tonewheel bleedthrough - is this normal?



My L also has it. but not very noticeable. </p>

Ground power is sticky topic, some are for it, some against. Hammonds use chassis grounding, if you introduce an external ground you may induce ground loop interference. Sometimes not though...Personally I like to keep them 2 prong, but I always replace old power cords.</p>

If you still wish to add ground, this usually happens inside the organ pre-amp or amp where the power terminals are soldered. You need to find a bare spot on the chassis to secure the ground to, either with a screw or solder. Maybe George can clarify? He's the man.
</p>

[tonewheel1966]

Re: Tonewheel bleedthrough - is this normal?

My UK L122 is grounded but my UK (Later) T202 isn't?! I know from the L Manual that the Canadians ones were grounded.

[geoelectro]

Re: Tonewheel bleedthrough - is this normal?



My 2-cents on grounding is this. First, if it is not grounded but stock, and you're not having any problems with it, then there is no real need to ground it. On the other hand, there is no real problem adding a ground AFTER you check out some things. The AC comes in and goes through the outlet box, power switches and finally into the power transformer. As long as there are no failures, adding a ground to the preamp chassis is fine. However, if there is a loose wire on the power switches or a cracked AC wire laying on the generator (had that recently) or a leaking power transformer, you could be in for some breakers throwing after adding the ground. In the first page of most Hammond manuals, there is info on how to test your various chassis's for this kind of fault or leakage. As long as this test passes, then ground away.</p>

I bought the 3-terminal AC box from TrekII to ground a B-3. The reason was this organ was in a new church and had an orange weedeater cord on it. Not that that was any problem except the inspector seemed to think that a permanent piece of equipment that was being powered by a temporary power cord wouldn't pass inspection. So I was asked to put a permanent cord on it. The TrekII power outlet box is available with two or three terminals on it. I decided to try the grounded type which gives you the removable cord but with grounding. As I recall, the ground must go to the AC box and the preamp. Possibly more but that was a couple of years ago.</p>

Once connected, it popped a breaker as soon as I plugged it in. It seemed that a previous repair left a loose wire on the power switch so it could come in contact with the panel. Once that was corrected, all was fine.</p>

One other consideration. If you do not modify the Hammond, the wiring is stock and thus is grandfathered. If you change the wiring, and there is a problem with the wiring, you could be held liable for any damages. This is why many techs leave well enough along. Not to mention the possibility of ground loops that we all have to deal with using equipment with grounds. A tech in the UK told me that in his case, he would be liable if he didn't add a ground. You may want to look into your specific codes on this.</p>

George
</p>

[johnny b3]

Re: Tonewheel bleedthrough - is this normal?



Interesting stuff, George.</p>

[quote user="tonewheel1966"]I know from the L Manual that the Canadians ones were grounded.[/quote]</p>

My second L is canadian made (later model, with stamped drawbars and newer hammond logo) yet did not have a grounded power cord. </p>

[tonewheel1966]

Re: Tonewheel bleedthrough - is this normal?



Yep sorry meant to say after a certain serial number. Can't find it in the manual now!</P>
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