Hammond tonewheels

A bit about my Hammond T-202


Hammond T202/1
Hammond T202

I bought a Hammond Organ for £97

Yes! Organs are out of fashion, and take up space so most go very cheaply on ebay (pickup only!!!) If you know what to look for you can get a real electromechanical tonewheel Hammond Organ (Hammond also made loads of cheap cheesy transistor organs). Mine is a T-202 built in 1972. The T series is the last of the true tonewheel Hammonds. Many would-be “proper” Hammond owners pass over them because they have transistor amplification (so no dirty valve distortion like on your old Hammond records) But: it is very easy to put effects in the signal chain (including, for instance a valve preamp) AND you are much less likely to get an electric shock while you are mucking about in the back because valve electronics run on much higher voltages. ALSO the T-200 T-400 and T-500 all have an inbuilt rotary speaker – not quite a full Leslie but much better than nothing – almost all other Hammonds need an external Leslie speaker if you want that classic sound. The old B and C series had longer keyboards and were prohibitively heavy (mine is 235 lbs!). If you want to know more there are good articles here from Sound on Sound and Wikipedia.

Hammond tonewheels
Hammond tonewheels – an electromechanical wonder.


Here are some of mine! The little wheels are all spun by a single motor and are geared to different speeds. The bumps on the wheels create an AC signal in the red coils you can see next to each wheel, which gets amplified into a musical note. A T-202 Hammond Organ has 74 Tonewheels.


My Hammond was very dusty when I picked it up!

Cleaning and Oiling

Whilst hooving (dysoning actually) the dust I did knock a couple of connectors off (arrgh) but I managed to deduce where they should be – next time I’ll photograph everything first so I know where all the wires go.

Hammonds need oiling annually and the oil travels from little funnels to all the tonewheels down bits of cotton – you have to use special oil because some oils have elements that would clog up the capillary action of the cotton. (You can see the little white funnels for the “Hammond oil” in the “Hammond T-202 top/back view” picture below). Mine had a tube of “Hammond oil” fastened to the inside but you can buy it on-line easily enough.

Lots of the Drawbars didn’t work properly – each one is effectively a volume control for a different tone, and they were scratchy at best! All I had to do was spray “Servisol” (a switch cleaner) into the drawbars from the back (you pull all the bars fully out and put the tube attachment into the top of the back of the drawbar) Many thanks to David Swain at Swain Electronics for help and advise on this.

Hammond rotary speaker
Hammond rotary speaker or Leslie

The inbuilt Leslie

My rotary speaker didn’t work at all but all it needed was a new speaker cone – I bought one from Swain Electronics for £18. Hammonds service manual refers to this as a Leslie, though I suspect Mr Leslie would disapprove. It does sound great – a 2 speed rotating baffle give a great splashy trem/vibrato sound but “real” Leslies also have a pair of rotating treble horns in addition to the speaker with rotating baffle – Hmmm rotating horns…. I am tempted to try making a set….

Hammond T-202 top/back view.

 Modifying a T series

Many Hammond owners want the sounds made famous by the likes of Jimmy Smith, Jon Lord, Booker T, Steve Winwood etc. Hammond spent some considerable effort cleaning up the sound of their Organs over the years – Distortion free amps and key click filters being two notable “improvements” – but perversely most players prefer the old sound! There is a very good article on how to make a T more like the B, C, M or other older Hammonds used by these players here. I have already done some of these mods and will do more, but I am more interested in getting a great sound than copying a particular other Hammond, they all sound a bit different anyway! Tony Banks of Genesis had an L series and then a T – the same as mine but without the Leslie. He famously dumped the external Leslie and used chorus and phaser effects to do a similar musical job but with his own unique stamp. I have been using a Boss GT-8 guitar multi effects pedal and all kinds of effects work splendidly. In case you want to do it yourself, pin 8 of the amplifier board is where I broke into the audio chain. This board is found on the floor of the organ just to the right of the volume pedal as viewed from the back. You can download a T-100 / 200 service manual here and Captain Foldback has some schematics here. if you want any more info contact me – I am more than glad to help if I can!



18 thoughts on “A bit about my Hammond T-202”

  1. Hi George, I picked up a T202 a couple of years ago for my studio, we haven’t used it much as it needs a bit of TLC, I found your piece very helpful & informative, and wanted to say thank……….

    So Thanks!!


  2. Hi George,i have got a t212 for free and of course i had to do some cleaning ( a lot of oïl )i have already done some of the captain’s foldback mods and i would like to put an in/out for effects
    like you have done.But elsewhere on the net they suggest the pin number 3 of the recovery board to break out the signal with a capacitor and a resistance !!
    How have you done yours ? is it Noisy ?
    I am not a great tech such as you.
    Your accordions are masterpieces… so wonderfull

    1. Hi Daniel, Thanks for the comment!
      I’m no great tech either but my break in point works well – not noisy (though my 202 is a bit noisy to anyway) – I’ve put various things in there from rack mount to guitar pedals. Not all the percussion is included – I think the Cymbal and Brush sounds must have a different signal path.

  3. I now own my late dads Hammond T 202, which has been operating well for me since 1999.
    Recently though the fast’Leslie’speed has been intermitant and now won’t work at all.
    Can you tell me what might be wrong, and how to fix it?
    I have been told by a bloke in the states that it sounds like relay trouble. When I turn the Leslie switch on and off though, I can hear a relay clicking; but still no fast leslie?
    John Harrison Wallasey, Wirral. England.

    1. Hi John – Sorry but I don’t know – maybe someone else will post an answer. I would check the switch itself, and have a look in the back at the mechanism to try and see what’s going on. There is also a link on this page to Swain Electronics who are very helpful. Good luck. George.

      1. HI, I had a similar problem with my T202 there are two motors on my leslie the slow motor ran no problem it was when I switched the fast leslie on that the trouble arose, when you switch on the fast leslie the fast leslie motor shaft moves forward to make contact with the slow leslie drive wheel and increase the speed what was happening with mine was the fast motor shaft was going to far forward and jambing the slow motor and bringing both to a halt , it was a simple adjustment I backed the fast motor off with two washers ,perfect hope this is helpfull.P.S it deose make yor neck ache trying to get to it,T202 are not easy to lift onto the bench good luck. Ray.

        1. Thanks Ray!
          Mine’s really inaccessable at the moment – surrounded by other gear but I plan to get in the back again this side of Christmas if I can.

  4. Hi George
    I too have a £100 T202 and though no musician I love noodling around on it!
    I have had to disconnect the drive belt for the vibrato unit on mine, as although it works it is very noisy. Oil doesn’t seem to help.

    2 things:
    I would like to do the breakout you describe – could you enlarge a little on ‘pin 8 of the amplifier board is where I broke into the audio chain.’ as I presume you have fitted an out and in jack sockets with straight through if nothing is connected.

    Secondly, you say you have done some of the other mods that ‘revert’ the T back to prior models tonally. What did you think of the results?
    I like the Banksy sort of sound of the T, but I can see that Jimmy Smith wouldn’t get on with one!

    Many thanks for your time.

  5. Hi George, Do you have any thoughts on why the pedals on my T200 and T400 play the wrong notes? They start off ok but very quickly into a tune, the notes seem to merge and I have to stop playing the pedals. It’s worse with the legato or sustain switched on.

  6. Hi George, This is the second T202 I’ve had, the first one was flight cased and belonged to hot chocolate. I didn’t really know much at the time but sort of dismissed it as it was transistorised. I have now been given another,with a leslie 125 with a valve amp. I have to admit to being a techie and am in the process of restoring and cleaning it up and may do some of the mods. I’d love to see if I can fir some horns to it. My fascination with the sound came from being sat in a dark room with my brother while he played dark side of the moon, and Focus. The sound of a leslie cabinet ramping up and down still raises hairs on my neck. Thanks you for your efforts and the resource

  7. Hi George. This is a great read. I recently got a T202 which I bought back to life and I’m thoroughly enjoying it. The built in Leslie’s a winner. Still getting crackly drawbars but not enough to find annoying. I did a little video for mine if you wanted to watch it as there aren’t many on the net which don’t have modification demos. Here the video https://youtu.be/ghbQQfYrtkc
    All the best and thanks for the knowledge.

  8. Hi George

    Just bought a 1970 vintage T200 and it has the connectors and half moon switches for the external leslie too, it works ok having got the hoover out and cleaned the inside of dust etc, it only has one issue, the “G” pedal at times (not always) doesn’t sustain, it’s really annoying and I first thought a contact issue but the pedal plays ok without the sustain on so not sure what to think? any ideas??? how do you get to the pedal contacts anyway?


    1. Hi Dorian,
      Thanks for your comment – it’s taken me a while to answer so maybe you are sorted already which would be good because the short answer is I’m no expert on these and I don’t know. However I have a kind of idea because all the tones are being generated all the time and the keys and pedals are just switches that let the sound through to the amp. So sustain has to be a kind of electrical switch that doesn’t turn off suddenly which makes me think “capacitor” Capacitors are notorious for deteriorating over time so that’s my best guess. I have never looked at the pedal contacts so I don’t know how to get to those either sorry!
      Anyway – good luck!

  9. Hi all I am new here and have just started playing again after a 30 yr gap! I am getting a 1 owner T202 and have alredy bought a Leslie 125.
    What I neee to know is do i need anything else other than the 6 pin cable to connect the Leslie to the organ?
    I assume there is a connector on the back of the organ but do I need a half moon switch? If so are they easy to install?
    Any help and advice will be greatly received. Thanks guys the info on this site is great!

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