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Yellow Jacket Titan P51-870 Digital Manifold Teardown

Front Panel & LCD
Front Panel & LCD

New tool time! I figured now I’m a fully ticketed member of the F-Gas community, I’d treat myself to passing the course by buying a decent set of refrigeration gauges. This is the Yellow Jacket P51-870 Titan manifold, a fully digital unit with all the useful functions built in. Basically an electronic module attached on the top of the standard Titan manifold, this unit performs all the regular functions I’d normally need either a calculator for, or other tools. The front of the unit has just a power button, LED & a large resistive touch TFT panel for display.

Rear Panel
Rear Panel

The rear panel has the ports for charging the internal battery, which is micro USB – this is also used to download log data to a PC from a system processing run. There are 4 3.5mm jacks for the external temperature probes, and vacuum sensor.

Rear Cover Removed
Rear Cover Removed

Removing 4 Torx screws in the back panel allows the clamshell case to come apart, showing the mainboard, and the pressure transducers screwed into the manifold. The aux jacks & the USB charging & data port are supported on small vertical PCBs plugged into the mainboard via 0.1″ headers.

Main PCB Overview
Main PCB Overview

With the pressure transducers unplugged from their looms to the mainboard, the module is free from the manifold section.

Main Microcontroller
Main Microcontroller

The muscle of the operation here is a Freescale (now NXP) Kinetis K2 Series MK22FN512VLH12 ARM microcontroller. With a Cortex-M4 core at 120MHz, there’s a bit of beef here. The LCD & touch overlay is controlled by a Bridgetek FT810Q Embedded Video Engine. The video controller communicates with the microcontroller via SPI, and the LCD via parallel RGB. There’s some SPI Flash memory up on the left, for log data storage, a Winbond W25Q32JV 32Mbit part. Just under that is a pressure sensor, which I’ve been so far unable to pull a part number off. This is required to assist in calibration of the main pressure transducers.



Switching Section
Switching Section

In the top right corner of the board is a 74HC595 shift register, with quite a few discrete transistors & diodes hanging around it. I suspect this is used to switch between two vacuum sensors when both are plugged in – from looking at the waveforms present on the sensor interface, the power does appear to be switched ON/OFF on a single sensor at about 1Hz.

My guess at the moment is that the sensor communications are over I²C, by the 4-wire connection, and the very obvious clock & data line on the connector, but I haven’t yet looked deeply into this.

Main Power Supplies
Main Power Supplies

Next to the battery connector (the battery itself is a single LiPo pouch cell, double-sided taped to the front shell, behind the display), are a selection of DC-DC converters, providing all the required voltage rails. No doubt there’s lithium charging control going on here too.

Bluetooth Module
Bluetooth Module

Wireless connectivity is provided for by a Silicon Labs Blue Gecko BGM111A256V2 Bluetooth 4.2 SoC module. These are also fairly powerful parts, with a full ARM Cortex M4 microcontroller hiding inside, clocked at 40MHz. There are as a result two programming headers on this board, in the top left corner, for both this part & the main microcontroller.

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HP 5087-7048 Directional Coupler Teardown

Directional Coupler
Directional Coupler

Time for some more RF component teardowns, here’s a very high quality Directional Coupler from HP, I believe this was part of a Vector Network Analyser at some stage. The main body appears to be made of Brass, but the entire unit looks like it’s Gold plated – the shine is far too good to be just Brass! Connections are via SMA connectors.

Label
Label

There isn’t much on the label to explain what the specifications are unfortunately. Nothing that can’t be found out with a quick look on a VNA though.

Cover Removed
Cover Removed

After removing the 6 Torx screws securing the top cap of the coupler, the internal components are revealed. There is no RF gasket or seal on the top cover, and relies on flat machining for an RF seal.

Internal Components
Internal Components

The internal construction of this unit is a little different from what I’ve seen before in directional couplers. The arrangement is usually parallel copper tracks on a suitable RF substrate, but in this case, HP have used a very small diameter Coaxial cable, covered with ferrite sleeves on the outer shield. The large square block in the middle is rubber, and may just be to stabilise the assembly. It may also be loaded with ferrite powder to give some RF properties too.
The ferrite cores are secured in place with beads of black silicone, again probably to prevent movement under vibration.

Input End
Input End

The input of this coupler is AC coupled via a capacitor, and then fed into the centre core of the Coax. The forward power output pin, visible at the top of the track, is coupled to the centre core of the coax by a tiny carbon track making up a resistor, via another ceramic capacitor. The track is more directly coupled via another carbon trace to the outer shield of the Coax. I believe this coupler is damaged, as the carbon trace that goes via the capacitor has a break in the centre, but the coupler does seemingly still work.

Output End
Output End

The other end of the coupler is very similar, although with no main line coupling capacitor, it’s direct fed to the SMA here. The reverse power output is connected the same way as the other, with a network. The carbon trace here though doesn’t have a break.

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Housekeeping – Moving Servers!

The time has come yet again, to reduce my rack footprint. For the last 5 years or so, this blog has been hosted on a small HP MicroServer Gen8, as at the time I needed a new host machine, and for some reason they were going by their thousands for rock-bottom cash. That machine has faithfully worked 24/7, without many gripes, but it’s time to concentrate things down to requiring less physical hardware.

What’s enabled me to sort this out, is performing a hardware rebuild on my main file server, which has for years been a Heath-Robinson affair.

GPU & RAID Cards
GPU & RAID Cards

Well, the file server got ANOTHER upgrade, quite quickly. The motherboard was replaced again, this time with a new board, new Corsair RAM & a new Intel i7-9700F 8-Core CPU. As this server also runs video transcoding services, the tiny GPU got pulled & replaced with a spare nVidia GTX980 I had just for that task. My LSI RAID cards are still used as HBAs, just as JBOD, since Linux is running the main disk array via mdadm.

Server Internals
Server Internals

Once this upgrade was completed, with space for resource expansion – the motherboard supports up to 128GB RAM, at the moment there’s 32GB in there due to the eye-watering cost of RAM at the present time – there was scope for running some Virtualisation for other services.

Still running OpenMediaVault, based around Debian 10, I installed the Kernel KVM modules & QEMU, along with Cockpit for control. Going this route was dictated by VirtualBox not being directly supported in Debian 10, for reasons I don’t know.

Once all this was installed, and a network bridge set up for the VMs through a spare network interface, I brought up a pair of Debian 10 servers – one for PiHole which had up until this point been running on a spare Raspberry Pi for the last 6 or so years (I think the SD card is totally shot at this point!), and one for my web App server.

At the moment, all the VMs are running from the main RAID6 spinning rust array, which is a little slow, but the next planned upgrade is to move the VM subsystem to it’s own RAID10 array of disks, hopefully speeding things up – there are just enough SATA ports left on the motherboard to accommodate 6 more drives, and with both 5.25″ disk bays being available for caddies, this should be a simple fix.

As a result, I’m down to a single server powering my entire online domain, and a reduction in power usage!