ad: CQRHam-1

Laptop emergency power

Discussion in 'General Technical Questions and Answers' started by K2CQW, Oct 12, 2018.

ad: L-HROutlet
ad: l-rl
ad: Left-3
ad: abrind-2
ad: Left-2
ad: l-BCInc
ad: l-gcopper
ad: Subscribe
ad: L-MFJ
  1. K2CQW

    K2CQW Ham Member QRZ Page

    I have a whiz bang sla battery to power my FT450D, FTM400XDR and Pakratt232. However, my Acer laptop must rely on its internal battery when the fit hits the shan. Is there a simple way to power the laptop from my battery? 73 from Delaware, proud to fulfil WAS for all.
  2. AG6QR

    AG6QR Premium Subscriber QRZ Page

    Most laptops need something like 19VDC, significantly more voltage than a ham radio battery produces. The cheapest simple solution is probably to get an inverter to produce 120VAC from the battery, then use the laptop's AC adapter. But that's not a terribly efficient use of limited energy stored in your battery. Probably more efficient to buy a laptop adapter to go directly from car power to laptop voltage.

    Any way you do it, a laptop is pretty power-hungry. In a true emergency, I plan to do without. In a minor inconvenience, I may power a laptop from an inverter or directly from a generator.
    K2CQW likes this.
  3. KV6O

    KV6O Ham Member QRZ Page

    You can usually find 12V adapters for most laptops, but you can build your own as well, search eBay for DC-DC converters and get one that can accept 12VDC, and output what your laptop needs - usually 18-19V these days. You'll need to make sure it can deliver the current you need.

    Big downside to this is the RF noise that can be created by a DC-DC switcher, that might take some work to tame...
    AK5B and K2CQW like this.
  4. KA5IPF

    KA5IPF Ham Member QRZ Page

    If TSHTF just what the heck are you going to do with your computer???? Very bottom of my LONG list. Water, food, shelter are at the top.
  5. WJ4U

    WJ4U Subscriber QRZ Page

    You order all that online with a computer. ;)
    KD2ACO likes this.
  6. N3HGB

    N3HGB Ham Member QRZ Page

    This isn't really a hard thing. Find any number of 12 volt car adapters for laptops.
  7. KA9JLM

    KA9JLM Ham Member QRZ Page

    These are available at a good price shipped via the slow boat.

    DC-DC Adjustable Boost Converter Step-up Power Module 10-32V to 12-35V 150W 6A
    AK5B and K2CQW like this.
  8. WB2UAQ

    WB2UAQ Ham Member QRZ Page

    Aren't these 12VDC to 120VAC modified sine wave units at efficiencies of >95%? If so why bother building a 19V DC supply?
  9. N7EKU

    N7EKU Ham Member QRZ Page


    Just first make sure that the laptop will run with plain DC. My Dell ones will run on a DC supply, but won't charge the laptop battery because their supplies have ID chips in them that the laptop looks for. If you can find a dead (genuine) adapter, you can use the cord and internal PCB to run off a DC supply while keeping the chip in line.


  10. KA9JLM

    KA9JLM Ham Member QRZ Page

    A UPS would be the best way to go.
    K2CQW likes this.

Share This Page