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Labgear PSM114E/S 12v Conversion

Onboard the boat we have a small issue with a weak TV signal, and this coupled with a 60′ long run of coax is an issue. Due to the loss in the coax, we’ve lost most of the already weak signal.
To try & solve this issue, I’m fitting a masthead amplifier unit.

These amplifiers are fed power down the same coax that’s carrying the RF signal, and a special power supply is supplied with the amplifier for this. However it’s only 240v AC, no 12v version available.

Here’s the power supply unit, which fits into the coax between the TV & the antenna.

Amplifier Supply
Amplifier Supply

Luckily the 240v supply is easily removable & here has been replaced with a 12v regulator.

New Supply
New Supply

There’s not very much inside the shielding can, just a few filter capacitors & an RF choke on the DC feed, to keep the RF out of the power supply system.

The original cable is used, so the supply doesn’t even look like it’s been modified from the outside.

More to come on this when I get the amplifier installed along with the new coax run 🙂

73s

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nb Tanya Louise Hydraulic Generator

Hydraulic Generator Unit
Hydraulic Generator Unit

To accompany the previous two posts about hydraulic generators & their components, here is the actual generator unit itself.

Rated at 8.5kVa 230v AC, this will providea mains supply while the narrowboat is away from her home mooring.

This unit will be attached to the side of the hull in the engine room on rubber vibration isolation mounts, behind the main hydraulic oil tank & is driven from the small gear pump attached to the back of the main propulsion hydraulic pump unit.
Operating pressure is 175 bar, 21L/m flow rate to achieve the 3,000RPM rotor speed for 50Hz mains frequency.

Generator Specifications
Generator Specifications
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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.