SC145, v1.1, Assembly Guide

Click here for a list of the parts required to build an SC145, v1.1, Compact Flash interface for RC2014.

Experienced builders should decide on the prefered orientation of the Compact Flash adapter and then just go ahead and populate the board. There shouldn’t be any surprises to catch you out.

Horizontal (straight header)
Vertical (angled header)

Getting started

This guide assumes you are familiar with assembling circuit boards, soldering, and cleaning. If not, it is recommended you read some of the guides on the internet before continuing.

First check you have all the required components, as listed in the parts list.

Before assembling it is worth visually inspecting the circuit board for anything that looks out of place, such as mechanical damage or apparent manufacturing defects.

If you have a multimeter that measures resistance or has a continuity test function, check there is not a short on the power supply tracks. Connect the probes to each terminal of one of the capacitors, such as C1. This should be an open circuit, not a short circuit.

The picture below shows what a completed SC145 should look like.


Fit and solder the 1k resistors, R1 to R4, shown below in red.

Fit and solder the 100R resistor, R5, shown below in green.

Resistors can be fitted either way around, as they are not polarity dependent.

IC sockets

Fit and solder the IC sockets.

Be sure to fit them with the notch matching the legend on the circuit board, so you do not end up fitting the IC the wrong way around too.

Light Emitting Diode (LED)

Fit and solder green LED, LED1.

If using an angled LED the polarity is predefined and matches the PCB.

If using standard LEDs care must be taken to ensure they are fitted the correct way around.

It is important to fit the LED the correct way around. LEDs usually have a small flat side to indicate the cathode (the negative end). This should be positioned to match the flat side shown on the circuit board (illustrated to the right). Also, the cathode pin on the LED is usually shorter than the other pin (the Anode).

Capacitors (100 nF)

Fit and solder the 100 nF cacacitors, C1 to C3.

These can be fitted either way around as they are not polarity dependent.

The exact value of this component is not critical. The use of very cheap capacitors within the range of about 30 to 200 nF is acceptable.

Capacitor (100 pF)

Fit and solder the 100 pF capacitor, C5.

These can be fitted either way around as they are not polarity dependent.

Single row angled header pins

Fit and solder the single row angled header pins, P1.

Capacitor (100uF)

Fit and solder capacitor, C4.

It is important to fit this capacitor the right way around. The negative terminal is indicated with a ‘minus’ sign, as illustrated to the right. The negative terminal also has a shorter lead.

The silkscreen has a plus sign for the positive terminal and a hashed area for the negative terminal.

IDE connector

Fit and solder the IDE connector, P2. This can either be right-angled or straight, and either a box header or header pins. The box header is recommended.

IMPORTANT: Note the position of the key slot on the box header. This must match the position indicated on the circuit board.

Fit a straight header if you want the Compact Flash card to be parallel with the backplane. This is likely to be the best option if you are using the module with a motherboard-style system, such as SC114, SC126, and SC130.

Fit an angled header if you want the Compact Flash card to be perpendicular to the backplane. This option means the Compact Flash is mounted very high above the backplane, but it can be installed in the middle of a backplane. In this case, the Compact Flash card faces the solder side of the module which may not be very visually pleasing.


Remove any solder ‘splats’ with a brush, such as an old toothbrush.

Visually inspect the soldering for dry joints and shorts.

Clean the flux off with suitable cleaning materials.

Visually inspect again. The importance of visual inspection can not be overstated.

Quick Test

Check for a short on the power supply tracks by measuring the resistance between IC U2 pin 14 and U1 pin 7 (indicated below). This should be an open circuit, not a short circuit. If you are using a digital meter set to measure resistance it will likely take a few seconds for the reading to stabilise as there are now capacitors on the power lines. A reading of more than 100k Ω (100000 ohms) is acceptable.

Integrated circuit

Insert the integrated circuits (ICs) into their sockets, taking care to insert them the right way around, as illustrated below. Be careful not to bend any legs over. ICs are usually supplied with the legs slightly spread outwards so you may wish to bend them to the 90-degree position before inserting them into their sockets.

You are now ready to give it a try.

Getting Started

The SC145 User Guide can be found here.

Other information about SC145 can be found here.

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