How should I go about dimming a F15T8 fluorescent lamp on 120V 60Hz ? Is there an (easy) way to accomplish this with readily available parts ? I am not really well versed in electronics and I don't have a soldering iron. Maybe there exists a special ballast for this application.

I'd like to try dimming fluorescents (any size) but the ballasts and 0-10V dimmer prices are not in the budget at the moment.

That request is not too complicated

 First u will need two transformers
About sbout 6 -7 volt output will do.
As this will heat the cathode like
U  do in rapid start.  A normal
Preheat choke  with out it starter
Circuit . And a Fan Speed controller
Ithst should get you started for experments
In dimming fluorescents.

Most fan speed controllers are leading edge cutting dimmers, i.e. they cut the sine wave shape. At some stage of dimming the delays are going to be long enough that the tube might fail to restrike after zero crossing, so get flickery or go out. That is without starter

With starter the dimming may stop working at still brighter setting, when the tube would still be able to restrike if it was alone, but the starter is easier choice then the starter lights up instead and starts clicking and shorting out the tube

So if you try to dim beyond what the fan controller can, you'll need a variable inductance or a rheostat in series with the choke. For some preset brightness just use lower power choke or chokes in series

I wouldn't use the "cutting" dimmers because they could cause ballasts to break if not designed for them, because of the sharp voltage transitions.
It could probably be compared to MSW inverter power.

They wont break a ballast that easy, but the dimmer would break from the ballast's back EMF. This is not a problem with dimmers that allways open the circuit at zero crossing ie. leading edge dimmers

@funkybulb : I believe there existed a kit for European chokes that did exactly that. I assume you mean transformers that have a 120V primary and a 6-7V secondary ?

@everyone : Thanks for your input, will go on the "when I have time" list.

Yes Sol tha correct as u will need two of them
As  one centertap transformer wont work
As. Current wont go though the lamp
That why u need tw0 120. To 6 volt
Step down transformers.
Once cathodes heated u can even
Send high voltage audio though
It. Watch the lamp modulate
With the audio beats if u really
Want fo that far lol

If you suffice with step dimming (and you do not need to have it continuous), a series capacitors with the ballast inductor would do the trick.
But you may need some momentary switch for the initial arc ignition - I doubt the 120V would be enough to strike it, even with hot electrodes, but you may try.
For a "100%-50%-25%-14%" you need a "3-way" switch, one 2uF and one 1.2uF capacitor (both rated for at least 250VAC).
The switch has one lead marked as "Line in", one as "Low" and one as "High" and two contacts, one between the LineIn and High (On at "medium" and "high" positions), one between LineIn and Low "ON at "low" and "high" positions. You probably know these, but I wanted to define it's terminal names I would be using in this descriptions, so you may link that to your switch.
So connect the 2uF capacitor between "LineIn" and "Low", the 1.2uF one between the "LineIn" and "High". Then connect this contraption in seris with the ballast choke via the "High" and "Low" wires.
What it essentially means:
When both contacts are ON (at "High" switch position), both capacitors are bypassed, so the lamp is ballasted just by the series choke.
When at "Medium", the 2uF capacitor becomes in series with the choke (the 1.2uF bypassed). If my calculations were correct, the 2uF should have about 3x higher reactance than the choke, so that means the total ballasting impedance would be 2x to the original ballast, hence the 1/2 current.

When the 3-way switch would be at "Low", the 1.2uF cap becomes in series with the choke, (the 2uF bypassed). That means capacitive reactance about 5x the choke reactance, so total it is 4x to the choke alone, so hence the 1/4 of the rated lamp current.

And when the 3-way would be in "Off", both capacitors would be in series, so forming 0.75uF total. That means 8x higher reactance than the choke, so together it means 7x higher ballast impedance, so 1/7 of the rated lamp current.


You may play with the capacitor values, but I would keep the ratio of the brightness levels about factor of two - that I would see as quite a good compromise between the brightness differences (don't forget the eye is logarithmic, therefore the ratios should be about the same) and the total control range.