Work Day 18th January 2020


Work continued on preparing the pedestal and aerial system for a repaint. The Radiation Absorbent Material (RAM) on the top section of the pedestal has been refurbished by filling cracks and then rubbing down. The aerials are currently on their back so preparation work was carried out on the waveguides, aerial boom and the area around the top junction box and inside face of the elevation gearbox. See accompanying photos.

T86 Ae System Refurb.jpg

T86 Pedestal Refurb.jpg

The refurbishing of the top junction cover box has been completed, apart from fitting new rubber tubing from the vents to the desiccator. See attached photos.

T86 Top Dist Panel Refurb 2.jpg

T86 Top Dist Panel Refurb 3.jpg


The positive and negative 6V DC power supplies in the display console are stable again following disconnection of the Dish/Launcher box. This unit is not used in the simulator mode so finding the fault that is affecting the power supplies can be left until the team has more time.

Work has started on preparing the internal walls of the LCP for a repaint. The accompanying photo shows the general condition of the walls, paint has come away at the roof join and is in generally poor condition.

LCP Int Wall Rub Down 1.jpg


Away from Cosford at 3rd Line

1. SCSI Disk Emulator

The Argus 700 in the LCP now runs using a solid state SCSI disk emulator and a new version of the emulator is available which has been purchased and tested. The accompanying photo shows the test set up which includes the SCSI disk emulator under test, tape drive and tape controller.

Testing SCSI2SD.jpg

The assembly is connected to an Argus 700 and can boot the Bloodhound software. Testing was successful and the new SCSI disk emulator ran without a problem.

2. Fan Trays

I have finished refurbishing an I/O rack fan tray. We now have several spares of these trays so my plan this coming Saturday is to check the three in-situ I/O fan trays and the spare(s) in the LCP and check their fans. If any have fans that are dead or running slow I’ll swap out the fan trays to ensure all are ‘A’ OK.

The three fans in this refurbished tray were all refurbished a few weeks back but the tray itself needed some TLC. It was dirty, had patches of corrosion and the odd dead spider hidden in the cabling The fuse holder was broken and had to be replaced (good old eBay). The attached photos show the ‘kit of parts’ as dismantled and the other two photos the fan tray reassembled. The green dots on the fans cover the screws that dismantle the fan.

I sorted the A700 tray a few weeks back with refurbished fans. We have a spare A700 fan tray which I use on the test rig but it has 2 U/S fans.

Fan Tray Kit of Parts.jpg      Fan Tray Reassembled 1.jpg


Fan Tray Reassembled 3.jpg

A reminder … the computer racks use two types of fan:
EBMPapst 4650N – Argus 700 (six fans)
EBMPapst 4850N – I/O Rack (twelve fans)

The original fans were a mix of those that can be refurbished and those that can’t. Those that can are held together with two small screws, those that can’t are held together with two large hollow metal rivets (on the early models) which can’t be replaced by me at least. If the coil is O/C then the fan’s dead which was the case on a recent fan failure on the Argus tray.

The cost of new fans is another factor for new fans and we have looked at alternatives. Three X-Fans have been used in a spare unit for the base of the I/O rack but the nearest direct comparison to the Papst fans are supplied by SUNON. The SUNON has the same connector on the fan as do the Papst fans but … the air flow is in the opposite direction so can’t be mixed on a tray. The only requirement for new fans at the moment is for the spare Argus 700 tray and there’s no panic to get new fans at the moment. For info, Argus tray fans are:

Papst fans are £30 ish (they were a lot more but have come down in price)
SUNON fans are £18 ish

Cost makes a difference when six are needed to convert an Argus tray. Currently I buy individual fans as needed but they have to be Papst fans unless we replace all the fans on a tray (Argus six, I/O three).  … please note that all contributions are gratefully received as this project is totally funded from personal resources.

Pete H

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