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Solar Cable Upgrade & Pseudo-MPPT

New Cable
New Cable

As the cable supplied with the panel is far too short, inflexible & does not even allow the cable gland on the terminal box to form a seal, I have replaced it with some high quality twin core guitar cable, with silicone insulation.

The cable is removable from the panel tail by means of a screwlock two pin connector.

 

On another note, I have noticed a side effect of fitting a switchmode regulator to the panel: it seems to have formed an MPPT-type regulator setup, as even in low light conditions, when the bare panel is outputting 18.5v at 50mA short circuit, with the switching regulator I can get a useable 13.25v at ~170mA.
This effect is increased in full light, where I can obtain 4.5A short circuit current & ~1.8A at 13.25v output.

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He-Ne Laser

He-Ne Laser Mount
He-Ne Laser Mount

Having had a He-Ne laser tube for a while & the required power supply, it was time to mount the tube in a more sturdy manner. Above the tube is mounted with a pair of 32mm Terry Clips, with the power leads passing through the plastic top. The ballast resistor is built into the silicone rubber on the anode end of the tube. (Right).
Output power is about 1mW for this tube, which came from a supermarket barcode scanner from the 90’s. The tube is dated August 1993 & is manufactured by Aerotech.

Internals
Internals

Inside the box is the usual 2.2Ah 12v Li-Po battery pack & the brick type He-Ne laser supply. The small circuit in the centre is a switchmode converter that drops the 12v from the battery pack to the 5v required for the laser supply.

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AutoFace HID Ballast & Bulb

Ballast
Ballast

I bought one of these cheap HID kits from eBay to build a high-brightness work light that I could run from my central 12v supply.

At £14.99 I certainly wasn’t expecting anything more than the usual cheap Chinese construction. And that’s definitely what I got 😀

Potted PCB
Potted PCB

The casing is screwed together with the cheapest of screws, with heads that are deformed enough to present a problem with removal.

As can be seen here, the inside of the unit is potted in rubber compound, mostly to provide moisture resistance, as these are for automotive use.
The ballast generates a 23kV pulse to strike the arc in the bulb, then supplies a steady 85v AC at 3A, 400Hz to maintain the discharge.
This module could quite easily be depotted as the silicone material used is fairly soft & can be removed with a pointed tool.

 

Hi-Lo Bulb Assembly
Hi-Lo Bulb Assembly

Here is the bulb removed from it’s mount. Under the bulb itself is a solenoid, which tilts the bulb by a few degrees, presumably to provide dim/dip operation for a headlight. This functionality is superfluous to my requirements.

Bulb
Bulb

Closeup of the arc chamber of the bulb.