For ignition you need higher voltage

The 70W SON-T arctube is not the same as in the SON-E/I lamp with built in glow starter - It has different gas fill, more similar to what's in bigger SON lamps, which makes it only possible to start with the electronic ignitor (or atleast, a good enough hack substitute) but not a glow starter. The advantage is that it is more efficient, giving out some 1200Lm more than the lamp with the internal ignitor, and possibly a little better light spectrum too

There are a few possible ways to try to start the lamp without the proper ignitor though : (Note : Haven't tried any myself)

 - With a PZT generator (the spark generator from a lighter, based on a piezo element and a spring), applying the voltage capacitively to the center of the arctube from the outside of the lamp. (Do this from the side away from the internal lamp frame, so the frame won't sink the pulse)

 - With a homemade superimposed ignitor, wired same as any proper superimposed ignitor (in series with the lamp). For this you'll need to wind a ferrite pulse transformer with primary and secondary windings, and supply a pulse to its primary using a charged capacitor. (An obvious warning : You must be careful with building and operating your own ignitor, because it involves high voltage at energy levels that are dangerous)



70W SON (both SON-T or SON-E with internal ignitor) run at 1A 85V. A better ballast for this lamp would be 3x "18W T8" chokes in parallel, or 6x "13W PL-C" chokes in parallel

The 2x 36W T8 ballast will only supply about 0.9A or so (to my estimate) so underdrive the lamp (not by a whole lot, but probably enough to reduce its light output and get more SOXish color), and the ballast itself will overheat a little (not critical for short term experiment tho)

I think I'll just buy the ignitor because it is way too complicated or risky to do, although I wonder if an auxiliary 18W ballast in parallel with a 1.5uF capacitor in series with a starter and all that in parallel with the lamp would work. The choke should generate a high voltage spike and the capacitor should keep oscillating extending the high voltage pulse.

Probably a bigger capacitor in parallel with the starter with the current setup would work.

Sent you a PM.

I found this HID ignitor at Mercadolibre Chile at a very accessible item+shipping price, so I'll probably buy it.

@WorldwideHIDCollectorUSA will it work if I keep using the 2x 36W chokes but with a proper ignitor? Will an 18W ballast work instead of a 13W one as an extra?

If I don't manage to get the ignitor what would be the best replacement?

An 18w ballast might work as long as it is a PL-C ballast and NOT a T8 ballast.

An 18w ballast might work as long as it is a PL-C ballast and NOT a T8 ballast.

Is there much current difference between a PL-C and a T8 ballast? Also, can I run a probe 70w MH with 2x 36W chokes, if such lamp exists? Can I run MV lamps using the same fluorescent chokes hack?

Is there much current difference between a PL-C and a T8 ballast? Also, can I run a probe 70w MH with 2x 36W chokes, if such lamp exists? Can I run MV lamps using the same fluorescent chokes hack?

You might be able to run an 80w MV lamp using 2 36w chokes in parallel.

The 18W T8 is 370mA 57V
The 18W T8 choke can also run some lamps with arc voltage around 100V, in which case the current will be ~320mA. Specifically 26W PL-C and 28W 2D

The 18W PL-C is iirc 220mA ~100V (dont remember the exact voltage)

The 13W PL-C is 165mA 91V



The 70W SON is a 85V lamp, so it will get something between 320mA and 370mA with an 18W T8 choke, as the voltage is between 57V and 100V

It is also fairly close to the 91V of the 13W PL-C, so it will get close to 165mA (a little more) with the 13W PL-C choke

For 1A, we get 3x (~340ish mA) = ~1020mA, or 6x (~165 mA) = 990mA, both close to the 1A for the 70W lamp



The 18W PL-C works at 220mA. The 18W PL-C choke at short circuit will only give some 300mA or so, and less with a lamp (any lamp). So it can't run an 18W T8, that requires at least ~350mA. With a 85V SON-T it will run at something between 220mA and 300mA, so if it would be going to work, it would need maybe 4 chokes in parallel to run the SON-T

However, since this choke is not meant to handle currents over 220mA (it is not designed for any lamp other than the 18W PL-C), it will overheat with lamps like 18W T8 or 70W SON, so only good for a short experiment with the SON-T

The 18W T8 choke will run at ~320mA with lamps with ~100V arc, so overdrive the 18W PL-C at 1.5x its normal power which is big overload for the lamp

@Binarix128, here is a listing for an electronic ballast that might run your 70w HPS lamp pretty well:

https://articulo.mercadolibre.cl/MLC-524958037-balastro-electronico-70w-haluro-metalico-funcionando-_JM#position=1&type=item&tracking_id=361592a3-d874-4c97-8767-f7c0590b914f

@Binarix128, here is a listing for an electronic ballast that might run your 70w HPS lamp pretty well:

https://articulo.mercadolibre.cl/MLC-524958037-balastro-electronico-70w-haluro-metalico-funcionando-_JM#position=1&type=item&tracking_id=361592a3-d874-4c97-8767-f7c0590b914f

Thank you a lot for searching it, and it's pretty affordable too!  I completely missed that listen when searching. 

Seems like you quite a good experience searching on mercadolibre. Had you ordered lamps there?

Thank you a lot for searching it, and it's pretty affordable too!  I completely missed that listen when searching. 

Seems like you quite a good experience searching on mercadolibre. Had you ordered lamps there?

I had tried ordering stuff from there but it requires that I use a latin american postal code.

Thank you a lot for searching it, and it's pretty affordable too!  I completely missed that listen when searching. 

Seems like you quite a good experience searching on mercadolibre. Had you ordered lamps there?

Were you able to get the ballast that I showed you?

Were you able to get the ballast that I showed you?

I didn't try to buy it yet.