Hi -
I’ve just started collecting SOX fixtures (well, just one street light at this point), and of course most all are 230v, making it a nuisance to plug in here.

I’m wondering if there’s any good step-up products on the market small and affordable enough to haul around or even attach to a lower wattage fixture. I’m really interested in seeing the effect of  cool lighting in different locations, so devices that could be carried around and set up safely would be nice. 

I guess even plug adapters and extension cables would also work, like at my sister’s, who just had 240v put in to charge their e-car.

I like building lights and wiring stuff, and learned a good lesson years ago from the electrician who hooked our electric stove into the breaker box.

“When you work with electricity, you can’t let it scare you,” he said. “Because if you do, it’ll go straight for your heart!”

Anyone out there found or seen any clever methods for (fearless) volts enhancement?

From the text I understand you are from the US and collecting SOX equipment from overseas (probably UK,...). That means you will have, beside the voltage, another problem: The mains frequency.
European ballasts are designed for 50Hz, but in the US you will have 60Hz. And the frequency there is of prime importance (it directly dictates the ballasting impedances), to change that, you would have to completely redesign the ballasts.
And that no transformer can correct.
If the ballast in question would be just a bare series choke, you may to some extend compensate by an elevated voltage (using 277V). But many SOX ballasts are of a hybrid form, so have both capacitors and inductors (I'm not talking about the mains power factor correction, but about really functional components), there is no way to compensate that just by the voltage (higher frequency means inductive impedances increase, so elevated voltage could compensate for it to get the same current, but capacitive reactance decreases, so it completely screws up the impedance ratios within the ballast).

The way I do it (in reverse, to operate US stuff in the UK) is to use a 12V to 120V 60Hz inverter, running this from a high capacity 12V power supply.

You could do this relatively easily in reverse, although as I already had the DC PSU it wasn't all that expensive, the inverter cost me just over $100 including shipping. But if you don't have the DC power supply, you'd have the additional cost of this, so depending on your personal financial situation, it might be prohibitively expensive.

It's an option to think about, though.

From the text I understand you are from the US and collecting SOX equipment from overseas (probably UK,...). That means you will have, beside the voltage, another problem: The mains frequency.
European ballasts are designed for 50Hz, but in the US you will have 60Hz. And the frequency there is of prime importance (it directly dictates the ballasting impedances), to change that, you would have to completely redesign the ballasts.

Well -- Looks like I won't be plugging those UK SOX lights into the dryer sockets! Good to know, I was thinking that the classic 50 Hz flicker would just get cranked up a notch. Not so simple!

Looking into actual frequency converters, they seem to start in the $450 range for 100w models. Hmm...

So I'm liking plan B from SOX35:
"The way I do it (in reverse, to operate US stuff in the UK) is to use a 12V to 120V 60Hz inverter, running this from a high capacity 12V power supply."

So basically (1) do the AC-DC sex change & divide volts by 10, then (2) reverse step 1 & multiply times 20. The inverters (for cars) seem pretty affordable, as SOX35 says.

And how about getting a proper ground to the light, since the inverter input is just 2-wire DC? Maybe directly connecting the source ground through a jumper to the ground of the light -- Also one of those fused UK plugs going to the light, just in case?

So basically (1) do the AC-DC sex change & divide volts by 10, then (2) reverse step 1 & multiply times 20. The inverters (for cars) seem pretty affordable, as SOX35 says.

I think I like that 

Yeah, you just need a reasonably sized 13.5V DC supply, ideally something intended to power 2-way radios or similar, the one we have is from my somewhat more active amateur radio days, so will power quite a sizeable load (32A continuous, 40A peak at 13.5V). That will power an inverter of up to around 600W quite easily, although the heat sink on the back does get rather warm when the 400W inverter we have is running at full power 

Or if you're not going to run things for long, then you could use a car battery or some large SLA batteries. Take a look at this battery powered 35W SOX floodlight that was posted a while ago..!

And how about getting a proper ground to the light, since the inverter input is just 2-wire DC? Maybe directly connecting the source ground through a jumper to the ground of the light -- Also one of those fused UK plugs going to the light, just in case?

The earth (ground) connection on the inverter output sockets (ensure you get a full sine wave inverter, not a modified sine wave or square wave one) is tied to the negative rail, which is in turn seems to be connected to mains earth somewhere in the PSU, it seems to work, anyway.

Hope this helps,

 I have been importing 240 volt 50z fixtures to the US here in Texas,  most of time 60 Hz have no problem with choke ballast
 But lamp runs at bit reduce current.  It best to disconnect power factor correction caps as it would be wrong on 60hz
 
  Now i did have lot of problems with capative leading circuit
  Such as my 8 foot pop pack.  Plus 125 watt lamps about non existant here.  But ive learn by changing cap value to a lower one works.  But i took it next step lower.  Got current down to 790 mA.  Ive been running American tubes in a 8 foot british pop pack ever since.  And running on 60 Hz.

 I just inported my gamma 6 sox so i will be doing some testing
On 60 Hz first.  Far as Transformers goes i started out using radio shack 300 watt step down transformer that u take with u on your travel.  But i cut the plug off and use a terminal block
And made a sucide cord to run step down transforner backwards.  Until I got my Jefferson  120/240 to 240/480 volt step up transformer.  That transfromer allowed me to have true
240 volt to ground,   None of this dryer outlet  stuff.  Also i can run my 480 volt street lights.   Sadly the SRS ballast i need use my inverter to run that lighting set up. 

Yeah, you can sometimes get away with running 50Hz stuff on 60Hz, but it's not 100% guaranteed, in any case my perfectionist streak makes me run lamps and ballasts on the correct supplies, even if it costs more money. It's also somewhat more difficult with 60Hz stuff on 50Hz. I just bought a 175W MH/MV ballast from Eric which cost $94 to ship, due to the weight, but to me it was worth it.

The thing is, fluorescents are quite tolerant to 20% underdrive, but SOX use to be thermally designed just on the edge to work.
Plus European fluorescents very raely use anything else than a series choke as a ballast, where the result of running at 60Hz is rather straight forward to imagine. If tye SOX you have use just a bare choke (plus the ignitor, but that is the only part working normally on either frequency) as a ballast, then it may operate "just" at the reduced current. But once a capacitor gets involved in any other way than just a power factor correction, there is no way for it to work without complete recalculation of the values.

True enough, although I do have a few leak transformers (one of which for the 135/180W lamps, has an essential capacitor in circuit). The smaller one for 45/60/85W SO/H and SOI/H lamps (which will also run 35W and 55W SOX quite happily, anything at 600mA really) only has a PFC capacitor.

I have a power supply and what looks like a pretty good pure sine wave inverter on order (Euro style).

Excited to see that in action - I'm hoping to light up the backyard soon!

What i do doesnt fix the 50/60 cycle issue, but when i need to run 240 or 277 off my 120v ac line.

Ill take out a 400 watt HID ballast that features different line voltage inputs. I hook up 120v as normal, and the 240v, 277v and 347v leads will become outputs at those voltages. I can connect a 240v device to the 240v lead and itll power a 240v device just fine. As long as the wattage is less than the ballasts rated watts.

This can also be done the other way if you have 240v power .the 120v lead will be active at 120v for a 120v load.

Lamps are not used on the ballast when used as a step transformer. Use a ballast thats higher wattage than the load you wish to step up or down on it or it work work right or fail.

The same technique is often used by HID fixture manufacturers to run the typically 120v 150w auxiliary halogen standby lamp on lumiinaires equipped for higher voltages. You can even see it mentioned on the label of some ballasts. 

I have a power supply and what looks like a pretty good pure sine wave inverter on order (Euro style).

Excited to see that in action - I'm hoping to light up the backyard soon!

Looking forward to it 

I have a variac that is 1000va. It can go up to 145v AC, but Im thinking of modifying it to go up to 277v.

Our big Variac (3kVA) will go up to 260V or so on a 240V supply, don't really need any more than that.