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Military Radios / AN/PRC-64A conversion to 80m band
« Last post by dannobyte on March 13, 2018, 11:33:58 PM »
Hello all,
Does anyone have info or experience with using an AN/PRC- on amateur bands?

Regards, dannobyte
General Discussion / Re: Yaesu FT-891
« Last post by STN on March 13, 2018, 03:43:05 PM »
Hi Gil
The "too high" position is a matter of perspective. I deploy each weekend regardless of wx, either qrp or qro- A solar panel is always part of the system. It is the only way to augment the current draw of our rigs. On a good day(8 months out of the year), I walk out of the field with a full battery! It doesn't have to be PowerFilm. I just thought it would be a smart investment. Remember, a rig (any rig) without a way to field charge it, becomes a boat anchor when batteries are dead.

I don't understand carrying a green radio 4x the weight of my 817 or 891, but has 0.18A current draw, when I can carry a lighter setup with solar panel and less weight. I also do not understand the KX2. Although small, it cannot be charged/discharged simultaneously while in the field.

Here are my two kits
Yaesu FT-817ND Primary GoKit
- FT-817ND
- 10w amp
- Powerfilm FM16-1200 1-2A Panel
- Genasun GV-5 mppt charge controller
- DIY 5Ah LiFePO4 pack with BMS

Yaesu FT-891 Field Station GoKit
- FT-891
- PowerFilm 120w 7.2A panel
- Genasun GV-10 mppt charge controller
- DIY 10Ah LiFePO4 with BMS

Both kits use a small 12v DC laptop running:
(All of these apps are well-suited for group communications on HF)
- APRS Messenger
- FSQCall
- FT8Call
- FLDigi

Regarding the battery question. Here is a better answer to your question.
The LiFePO4 chemistry curve is called "the hockey stick curve". It basically flat until nearly full discharge, then it drops like a rock. For the most part, it is like having two SLABS for one LiFePO4 pack of the same capacity. I know that's hard to get ones head around, which is why I made the capacity test video.

Thanks for the kindness. I am creating an operating methodology for various scenarios, "not a QRO system". Been a qrp operator for 19 years. Having a qro radio is not going to change that. ;)

I'm happy to support you through Patreon unless you plan on building another kit.
Would love to teach you some digital mode ops.

Julian oh8stn
General Discussion / Re: Yaesu FT-891
« Last post by gil on March 13, 2018, 02:58:28 PM »
Thanks Julian, that is a very interesting video. 1A on receive is much better than the 2A advertised. It's still too high in my opinion, but considering your whole system with the power pack and solar panel, you certainly found a way to do it. As you mention, it takes going out there to find out what works and what doesn't.

I wish there were more radios with around 30W output power and a reasonable current draw. Unfortunately, for whatever reason, there isn't much between 10W and 100W. Cost is an issue as well. I also wish I could afford a Power-Film, maybe later. My PRC-320 is great, but it has its drawbacks, and I still need to make a cable for digital operations.

FB on managing to create a practical QRO system!

Question: What voltage do you get out of your battery pack a few hours after a full charge?

Thank you for your Patreon contribution!!!

General Discussion / Yaesu FT-891
« Last post by STN on March 13, 2018, 01:25:53 PM »
Hello Operators
Topic of the day is the Yaesu FT-891. Many field radio operators have turned away from the Yaesu FT-891, because of the specs regarding current draw on RX, published on the Yaesu website. Since I have owned the Yaesu FT-857, and 897 in past years, the current specs for the 891, seemed somewhat off! In fact, I wondered if Yaesu simply published "worst case" numbers on the site, without bothering to publish a range of numbers which would make more sense to potential buyers. So, in this video we'll be measuring the current draw of the Yaesu FT-891 at RX, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100 Watts.

I've had many requests on the channel for such a video. Operators would like to compare current consumption to other popular rigs like the Yaesu FT-857D, Icom 7200, Icom 7300, as well as understanding how hungry this radio is when deployed in the field. Operators would also like to know why someone would choose a rig with a 1A RX current draw. Spoiler Alert! The truth is, we need to find the balance between QRP/Ultralight amateur radio, and QRO/when your life depends on getting the message out.

The truth is, the FT-891 weighs in slightly more than the FT-817ND with internal batteries. The LiFePO4 batteries I use can work with my 817 or 891. The trick to deploying a rig having such a current draw, is deploying with a lightweight solar panel and charge controller. I know Gil and I disagree on this topic but cheap is never going to be lightweight, and eventually, when your life depends on it, we all wish we would have purchased a thin-film flexible solar panel. No real survival minded person seriously thinks the ebay special from China with a built-in voltage regulator will do the job, but it is cheap! So I deploy both the 817 with a 20w thin film panel, and the 891 with a 120w thin film panel. The 120w panel runs my entire field station btw.

The following link is to my Yaesu FT-891 Current draw test.

This link is a playlist (which completely contradicts much of the gospel found here) on off grid solar and battery power for field communications.
Portable off grid power for amateur radio. amateur radio
Don't let the titles fool you. Everything I do is about extended field communications in a grid down scenario- The vanilla titles and tags help spread the word to a wider audience.

I do encourage everyone to get off the couch, get out in the field, and test their gear to near failure. Anybody can make videos, blogs or write forum posts. At the end of the day, it is field experience which will save your life.

Julian oh8stn
Antennas / Re: Revisiting the EA3GCY MEF-1 EFHW Tuner.
« Last post by gil on March 13, 2018, 06:14:50 AM »
Technical Corner / Re: New Steve Weber Project.
« Last post by gil on March 13, 2018, 04:23:27 AM »
Yep, I might start today if I solve an urgent issue on a client's database...

Technical Corner / Re: New Steve Weber Project.
« Last post by caulktel on March 12, 2018, 07:04:36 PM »
And so it begins :) I am just about finished with my uBitx and ready to start my Slop Bucket. Let us know all the mistakes NOT to make while doing ours.

Technical Corner / Re: New Steve Weber Project.
« Last post by gil on March 12, 2018, 01:17:30 PM »

Looking forward to your next post Andy, with photos!  ;)

uBITX has been shipped. Now the nail biting begins.
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