After a long search we have finally acquired huge stocks of the full range of Allen Bradley resistors. So hificollective are proud to offer you a broad range of values of the 0.125 watt, 0.25 watt, 0.5 watt, 1 watt and 2 watts.
For many many years these carbon composite resistors from the States have been held in high regard for hi-fi and for guitar amp use. Their natural organic tone is truely sublime. Unfortunately, production stopped in the 1990s and ever since then the stocks have been diminishing fast.
These "hot-molded carbon" resistors offer the simpliest of concepts for a resistor design. They effectively consist of a solid cylindrical carbon resistive element with leads embedded at each end. Making them incredibly rugged and highly reliable, together with their non-magnetic and non-inductive characteristics these little gems are remarkable in performance and sound.
If you pay close attention to the "Explanation of Part Numbers" diagram below you will see that there are various parts numbers employed for these resistors - engineers love their part numbers!. Firstly we have the Allen Bradley code (industrial type designation), consisting of 6 digits, this is what we use as the basis for our coding. The 0.125 watt codes start with BB, The 0.25 watt with CB The 0.5 watt with EB, the 1 watt with GB and the 2 watts with HB. These have their equivalent Military type designation that start with RC and then you have the Military Grade-S designation, that start with RCR. These are the creme de la creme of the Allen Bradleys, pls note we have ended our part number with R to denote this type. You also need to know that they have two resistive tolerances, 5% and 10%. Please note that these are NOS resistors and the actual true tolerances will be slightly more - please read the "special treatment" paragraph below on this.
Follow this sequence when purchasing if you have a choice, the best resistors are at the top of the list. The RCR code that has a "*" at the end means it is not a true RCR type. The partial code is given for those who are searching with part numbers.
- HB1805R: 18R 2W Allen Bradley 5%, RC42GF180J, RCR42G180JS
- HB1805: 18R 2W Allen Bradley 5%, RC42GF180J, RCR42G180J*
- HB1801R: 18R 2W Allen Bradley 10%, RC42GF180K, RCR42G180KS
- HB1801: 18R 2W Allen Bradley 10%, RC42GF180K, RCR42G180K*
PRICE 1 off
0.125W - £0.27+vat+p&p
0.25W - £0.32+vat+p&p
0.5W - £0.37+vat+p&p
1W - £0.90+vat+p&p
2W - £1.48+vat+p&p
0.125W - body: 1.5mm diameter x 3.8mm length. Leadouts: 0.36mm diameter x 25mm length
0.25W - body: 2.3mm diameter x 6.35mm length. Leadouts: 0.6mm diameter x 35mm length
0.5W - body: 3.5mm diameter x 10mm length. Leadouts: 0.8mm diameter x 35mm length
1W - body: 6mm diameter x 15mm length. Leadouts: 1mm diameter x 35mm length
2W - body: 8mm diameter x 18mm length. Leadouts: 1.15mm diameter x 35mm length
Allen Bradley RESISTORS special treatment method
As stated Allen Bradley resistors are carbon composite, being made of an organic material they do have the tendency to absorb water from the atmosphere. This absorption can increase the actual resistance of the component, hence the slightly higher than normal tolerance published on this page. To fix this simply remove the water from the component and seal it. The best method is to place the resistor/s on a baking tray, set your oven to 80 degrees centigrade and leave in the oven for 8 hours. The secret is to remove the mositure slowly if you rush it it will become noisy in circuit. Once cooked seal the body of the component in Shellack (preferably the flakes) to stop any further water absorption. At the end of this procedure you will have a much lower noise, more closely tolerance resistors. Special thanks to Colin Cornish for this excellent tip.