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battery suggestion for HW-9	Reply
by WA4IIF on May 22, 2008	Mail this to a friend!
I'm planning to use my old HW-9 for this year's FD. Does anyone have any suggestions for a light-weight and affordable (rechargeable or no charge) battery that I could use with the rig? The HW-9 power requirements are 11-16 volts, 1 amp. I'd use the battery only to power the HW-9.

RE: battery suggestion for HW-9	Reply
by WB6BYU on May 22, 2008	Mail this to a friend!
I've operated my HW-8 and Argonaut 505 for Field Day using a 4.5Ah gel cell, though I'll admit that I wasn't on the air the whole time (cooking meals, sleeping, etc.) If the HW-9 is similar to the HW-8 then a common 7Ah gel cell should get you through. (This presumes you spend more time listening than transmitting, of course.) While these can often be found for little or no cost as pulls from hospital or UPS service, they aren't exactly lightweight (at least not from the perspective of a backpacker.) Figure about 6 pounds for a 12V 7Ah cell. Here is a page from the Mouser catalog that shows you some sample batteries with sizes, weight, and prices. http://www.mouser.com/catalog/634/2000.pdf Or you could go down to CostCo and pick up a cheap pack of alkaline D cells. 9 or 10 of them in series should give you plenty of power for the weekend. They have a higher internal resistance than most rechargable batteries so the voltage doesn't hold as constant as the battery discharges.

RE: battery suggestion for HW-9	Reply
by K1JAW on May 22, 2008	Mail this to a friend!
I had a HW9 station and sold it – my loss. There are too many questions to answer you directly, but let me see if I can put you on the right track. Here are some sample numbers. How many hours do you plan on operating 24 X How much current does your HW9 draw in receive .2A = 4.8 amps How many minutes per hour are you transmitting * 6 X How much current does your HW9 draw in xmit 1A X 10% 0f 1amp x 24 (6 minutes/ 1 hour=10%) 2.4 = 2.4 amps Total battery requirement (4.8 + 2.4 ) 7.2 amps * Keying duty cycle, listen time, socializing time, etc Are you really going to have the HW 9 on for 24 hours? Is key-down for 6 minutes per hour realistic for your style of operating? Are you using solar panels during the daytime to partially charge your battery? Are you using headphones? One last comment. Be sure to have a dvm / voltmeter with you and stop operating if your battery reached 11.5 volts. If you need any additional information, feel free to email me. I now have an Elecraft k1, 8 amp hour gel cell, and a 4 watt solar panel and operate for a full week without problems. 73’s and enjoy QRP Jim

RE: battery suggestion for HW-9	Reply
by WA4IIF on May 22, 2008	Mail this to a friend!
Thanks for the catalog info. 73, Chuck

RE: battery suggestion for HW-9	Reply
by WA4IIF on May 22, 2008	Mail this to a friend!
Thanks, Jim, for the info. I'll plug in my "numbers" to figure my amperage requirement. I think a 12v, 7 - 8 amp battery should be more enough to last me during my planned FD operation. Please tell me more about your solar panel for recharging? Where did you get the panel? How does it work? Do you recharge while you're operating? I plan to do FD on a beach next to the Gulf of Mexico and hope there'll be plenty of sun available. 73, Chuck

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