This is a buy-in-now sale for a brand new replacement CMOS Battery pack, for the BBC Master 128 and BBC Master ET range of computers.

Is your BBC Master starting up incorrectly? Giving Error messages? You've reset your CMOS, but it won't save the setting overnight? You probably need to replace the CMOS battery pack with the ones available from RetroClinic.

The most common type of battery pack found in the Master is a sealed pack, in which the cells cannot be replaced on their own, the entire pack must be changed. Even in machines that have the 3 cell holders, if the batteries have started to leak, it is recommended to change the holder and the cable, as the alkali from the cell can corrode up the cable and onto the PCB connector.

So why not just go out and buy some batteries and connect them up yourself? There is a good reason why you should not. The BBC Master PCB was designed for a rechargeable battery in mind, and as such, when the machine is on, will attempt to charge any battery connected to it. For non-rechargeable batteries, this is very bad, and can cause overheating, or worse. To counter this, all BBC Master battery packs, including the one supplied here, is fitted with a diode, and current limiting resistor, to prevent back-charging.

This sale is for the standard 3xAA option, which takes 3 regular Alkaline batteries that can be purchased worldwide. The batteries are NOT included in this sale, you will need to purchase your own Alkaline cells locally. This type of battery pack usually lasts around 1-2 years depending on battery type and brand used before needing replacing.

The kit comes with the 3xAA holder, and the cable with the components fitted, as described above, along with complete fitting instructions, including how to reset your CMOS memory, and how to reset your Econet Station number, should you have an Econet system. The rear of the battery holder is fitted with strong self-adhesive padding, to fix to the inside of your case. The last photo shows the item, with batteries, sitting connected in a Master 128. Remember, the 3xAA cells are NOT included in this sale.

INTERNATIONAL SHIPPING: This item does not come with batteries, so can be shipped worldwide.

Due to 2nd class mail becoming more and more unreliable, all items are now being migrated to Tracked 48 postage. T48 and T24 postage on small items are usually free for any additional items of the same type. I am unable to get the system to automate combined postage for different items, however if you make the purchase for multiple different items using the basket method, I will combine them into one parcel where possible, and refund any postage excess at the time of shipping.

** UK POSTAGE BY ROYAL MAIL TRACKED 48 **