Because each person has a different way of visualizing where the positions of the slide trombone are in relation to each other, below are two different slide position charts which I hope will be helpful to those wishing to learn the positions of the trombone with a single valve in F and a second valve in D (Doug Yeo).
The first chart was created by Dr. Jurgen Faisst and shows a trombone slide and the location of positions for notes for the open, F and D valved trombone. This chart (chart # 1) along with a second chart (chart #2) by Dr. Faisst which builds a chromatic scale from the overtone series for each position, can be downloaded free of charge (PDF format) by clicking the links below:
Download trombone slide position chart #1 (PDF, approximately 60k)
Download trombone slide position chart #2 (PDF, approximately 44k)
The charts below give positions for notes for the "straight" tenor trombone in B flat (a trombone with no valves), notes which can be played on the "F attachment" (a trombone with a single valve) and the F/D attachment for bass trombone (a bass trombone with two valves in which a low "D" is the fundamental note in first position).
On the second chart below, a "+" by a number means the note should be played a little bit sharper (higher) than the position indicated, and a "b" (as in a sign for "flat") by a number means the note should be played a little bit flatter (lower). In the end, the best slide position chart is found in your own ear through a process of trial and error. The slide positions indicated are simply a guideline, and should be looked at in a relative sense with your ear as the final arbiter.
For bass trombonists wanting a slide position chart which gives positions for various tunings of the bass trombone (including various in-line and dependent configurations) I refer you to the "New Method for the Modern Bass Trombone" by Eliezer Aharoni, Bass Trombonist of the Jerusalem Radio Symphony Orchestra (published by Noga Music, catalog number 00175). It is the most comprehensive bass trombone method book available and benefits additionally from its excellent slide position charts. It may be purchased from any good music dealer such as Hickey's Music Center in Ithaca, NY (an excellent online music resource).
The the second slide position chart shown below was created by Chris Waage who is the associate webmaster of the OnLine Trombone Journal. I am grateful to Jurgen Faisst and Chris Waage for giving me permission to display and distribute these slide charts (Doug Yeo).