affordable batteries for the forklift
The BARETT forklift had had very little use for the past year because the 24v 600Ah battery died. I shopped around and a new one would be $2800 and a used one with about 60% life would be $2100.
I use the forklift 2 or 3 times a month and only for about 30 minutes total run time.
I calculated a commercial shop would expect about 2-3 hours of total run each day.
So, using idiot math I figured I was only using 100Ah on a big day.
A little research discovered that solar electricity systems need long duration deep cell batteries – much like the forklift. I needed 24v so two 12v 100Ah batteries in series would do the trick.
The forklift has a new life – albeit 30-60 minutes a day! It’s also about 1400 lbs lighter.
Oh yeah. I only spent about $360
A Catahoula at play. … perhaps that's redundant …
I have successfully created an APRS iGate using a Raspberry PI, RTL-SDR, mini WiFi adapter, SD card, and 5v micro-USB power supply.
I used several set of instructions from the internet including Marco Kubon’s blog post, Jason Fitxpatrick’s How-to-Geek wifi article, ReadiesCards thread on mini-httpd, and various debugging techniques that are best found by using Google if and when a problem exists.
The only reason I have the HTTP server integrated into the iGate is to make it easy to check the logs using any web browser, including from my iPhone and iPad. All maintenance is done using SSH. Like I said, “geek skills required”.
The hardware is all commonly available:
FYI: The cheaper and more common R820T based RTL-SDR dongles may work but I started with one of those and had issues. Then I switched to the E4000 tuner and managed to get things working. I did not go back and try to get the R820T based dongle working. Read into that what you want but given how much time I wasted on this project, I have not had the energy or desire to do more experimenting.
The one thing I will conclude with is that I do not yet fully trust this iGate. It seems stable but more than once – while getting the system working – I’d start up the software and it would not receive any messages. I think most of the issues are the lousy test antenna but I won’t know until I drop this in place of my stable 2m-radio based iGate.
Raspberry Pi, RTL-SDR, and PoE
Time to retract my opinion that you can’t make an iGate with an SDR and a Raspberry Pi. It turns out you can if you have the right software defined radio.
The most common RTL-SDR (USB radio receiver dongle) is the current crop of offerings which use the R820T chip for its tuner. These are also the least expensive at $10-$15 when ordered from any of the Chinese or Taiwanese vendors. The harder to find version uses an older E4000 tuner. These are also more expensive and many buyers have reported receiving a “free upgrade” when ordering the old style. Needless to say this causes problems since you really need the old E4000. In addition to looking for “E4000″ in the description, also look at the frequency range. It should be 50Mhz – 2200Mhz.
I finally took a chance and ordered a different RTL-SDR which claimed to be a real E4000 design. It didn’t look like any of the pictures others had posted for the “real deal” but the vendor claimed these were real. After 24 days on a boat, the little things arrived.
I tested them and they reported they had the E4000 tuner. The final test was to plug it into the Raspberry Pi, load the software test, and see if I could receive APRS messages.
IT DID !
The final packaging is not complete but the design uses PoE (power over Ethernet) and mount the small package near the base of the antenna and only run an Ethernet cable to it.