Causes for drastic change in battery drain on a Logitech wireless keyboard?

Question

I have an (at least) six year old wireless keyboard and mouse (Mouse is the Mx700) keyboard came with and they're pictured at the end.

Up until a few weeks ago when I changed a few things the keyboard had an amazing record of battery life it had some basic Duracell batteries in it that were almost a year old.

Now it's consistently not operational, flat batteries (trying other Duracell and Toshiba standard batteries, and newer rechargeable varieties; Enveloop, EverFast, DoCo, DuraCell (ranging from 1500mAH to 2800mAH).

The following has changed things have happened:

• I stopped using the mouse MX 700 (put away no batteries)
• Now have a G700 mouse connected.
• Reinstalled operating system (still Windows 7)
• Moved the receiver 30 cm further away. Line of sight still good.

Question 1

Could the mouse have been assisting in relaying the signal because it's closer, and thereby taking the power hit (it had horrible battery life as it aged). Now that it's no longer on the desk, keyboard has to communicate further?

Question 2

Before I spend some time trying to diagnose this problem does anyone have any obvious suggestions?

• Interference from new mouse?
• Or not worth discussing could just be age of the keyboard?

What I'll try first is brining the sensor closer again.

What hasn't changed:

• Usage of the keyboard is consistent
• No other possibly interfering devices in the room.

Solution

My Logitech K800 wireless keyboard ran a long time between charges until I replaced the landline phone on my desk with a Panasonic phone with DECT 6.0 Plus Technology. This caused the logitech keyboard battery to run down in a few hours. I put my old ATT phone back and the Logitech keyboard works fine again.

Comments

[Synetech]

This is amazing! I have the exact same set (keyboard and MX700). I too have been impressed with the keyboard's battery longevity, and I too have recently noticed it keyboard draining the batteries much faster than before. In my case, I suspect that there is a short-circuit in it that is effectively making it act as though a key is being pressed now and then. This is likely due to the fact that I have taken it apart (every single, last piece) two or three times and washed all of the rubber and plastic components, including the sheets with the etched wires, thus leading to rusting in the wires.

[Synetech]

Another thing I’ve noticed about the keyboard's behavior recently is that whenever I type certain things like cd blah or once there, it comes out as c dblah or onc ethere. You'll notice that the affected keys are e,d,c (the key registers after the space does) which are in the same “physically vertical row”. This behavior coincides with the fast battery draining. Does your keyboard act strangely like this? I think it probably fits the rusted wire theory. (Also, did you stop using the mouse because it no longer charged and would only have a rapidly flashing red-LED instead?)

[Nick Josevski]

@Synetech you and I are keyboard buddies now ;) I haven't taken any keys out to clean it only vacuuming. Ages ago I stopped using the base station, and would charge batteries in an external unit and just swap them in. When I finally stopped using the mouse it was because it would burn through fully charged batteries in < 2 days. Plus I wanted a mouse upgrade but still happy with keyboard except this battery issue.

[Nick Josevski]

Looking back I have experienced the e, d, c + space issue you described but didn't notice it, just assumed it was me mistyping. Will pay more attention now. I didn't have the rapid flashing on the mouse because of my alternate charging approach while it was in use.

[Lorenzo Von Matterhorn]

Wireless equipment is subject to interference, and therefore, the possibility of extra battery drain. this explains the situation you experienced.

[Davor Josipovic]

U find this strange. Can anyone confirm or explain this for this particular model (K800).