DSP Arrives

Well I was pleasantly surprised when my DSP turned up, firstly it had only taken 7 days from the date of posting in China, and second I was not hit for any import charges at all!

The declared value on the package was listed as just $10.00! As such it crept past customs without raising so much as an eyebrow.

Some other aspects that may have helped here are that firstly the package is relatively light at under 0.5kg (1lb) and that it was packaged in a previously used box that had seen better days, potentially as an additional effort to disguise the value of the contents.

I hasten to add that at no point did I suggest to the vendor that they de-value the item for customs, or suggest it was listed as a ‘gift’.

In fact the customs declaration does not even state what is in the box, which to me would have raised a flag of suspicion.

On opening the box, it contained the control panel, this additionally has a USB-B and CAT-5 network connection on the rear.

the controller

a breakout cable for the USB and CAT-5 network connections so you don’t have to use the ones on the back of the control panel.

an interconnect cable for connecting the front panel to the controller

a USB-A to USB-B cable

a CAT-5 network cable

some wiring quick disconnectors

and retaining clips for the front panel

No software or instruction manuals, but then I have already downloaded all of these from the Sinjoe website anyway.

A number of years back I bought a bunch of modular power barrier strips from RS which can be built up into any configuration you want from 2 to 200 connections, although in reality you would probably not want to go much wider than about 20 pairs of connections as it only secures at the ends.

I originally bought these for wiring my Beach Buggy, but had quite a few left over.

These comprise the following items:
2 row (£5.54 for a pack of 5)
3 row (£7.06 for a pack of 5)
Jointing segments (£2.89 for a pack of 10)
End Fix (£2.67 for a pack of 10)
Slotted Jumper (£4.00 for a pack of 50)
Straight and angled Tag connectors (can’t find these on the RS site)
(All the RS prices are exclusive of VAT at 20%)

These are intended for use with 3.5mm ring or spade terminal connectors which can potentially be stacked back to back or in combination with the tag connectors.

For the 220/240V power I thought that 4 rows for each of Live, Neutral and Earth should be sufficient

I used 4 x 3 row, 1 x jointing, 2 x end fix and 9 x Slotted Jumper pieces to bus each of the 4 rows together to produce the required connector block.

This then just happened to be the same spacing as between 2 of the 20×20 extrusions in the electronics side of the laser cutter.

The 24V PSU in this picture is not yet secured in place and may yet be positioned sideways.

The power rail has therefore cost me £10.00 ($15.50) inclusive of VAT, which whilst not as cheap as a 15A terminal block from a high street store (£2.00/$3.10), it is suitable for up to 15A at 750V and is far easier to bus terminals together without effectively clogging up one side of the terminal block with wires of a suitable gauge for 220V.

Plus, since I bought these barrier strips 10-15 years back, I effectively wrote off the cost ages ago.

I intend to replace the current printed mounts for the high voltage PSU as they do not really require ‘tags’ for the orientation I have used, the DSP Controller box will be mounted in a similar fashion on the same rails but towards the front of the laser cutter as shown here.

Unfortunately I have run out of blue filament and my usual supplier is currently out of stock, so these new mounts will have to wait a while.

I have also received a 1mm inductive NPN 6-36V proximity sensor from ebay seller sellerbible that cost me £2.48 ($3.85) with free P&P.

This will be used for autofocusing the laser lens, assuming I can find a suitable space to co-locate it next to the air hose on the X axis plate.

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