ASM-2 Construction Guide
ELBY Designs - Laurie Biddulph
9 Follan Close, Kariong, NSW 2250, Australia
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Bills of Materials (BOMs):
Components are given 3 or 4 digit identifiers such as C301, R221 and Q1201. The first of
these three digits (two in the case of 4-digit numbers) relates to the schematic sheet
number on which the component can be found whilst the last 2-digits are a sequence
number for that component category on the sheet.
When building your own order for components you should note the following points:-
1. All resistors are 1% 0.5W Metal Film (MRS25 Series). In most cases these can be
replaced by lower tolerance (up to 10%) resistors. Also in most cases you can also use
Carbon Film. The pcb footprint is for a 0.4” axial component.
2. Capacitors in the range 1nF and 1000nF are generally Polyester (BF or MKS2 Series).
Substitutes should be of a low-noise, high-stability type. The pcb footprint is for 0.2”
pitch radial components.
3. Capacitors below 1nF are generally 2.5% 160VDC Polystyrene (FCS Series) but
Silvered Mica will also work fine. In some cases it is possible too use a high-stability
NPO Multilayer Ceramic capacitor. The pcb footprint is for 0.2” radial components.
4. Decoupling capacitors are listed as 100nF X7R Multilayer Ceramics. Values in the
range of 47nF to 150nF can be freely used in these positions and any good quality
capacitor that will fit the 0.2” radial footprint can be used.
5. Capacitors of 1uF and above are polarised and should either be MDT or TAP Series
Tantalum or low-impedance Aluminium Electrolytics. Tantalums are, typically for 0.2”
pitch devices
Some schematics include panel-mounted components. Where shown, these components
are required for the proper operation of the circuit. These components are NOT included in
ASM2 Component Kit.
A hard-copy of the component overlay can be printed using this
file. It is sized for A3.
