BeeLine Interference Questions

Has anyone experience problems with the RF from a BeeLine transmitter causing interference or failures in altimeters, etc. sharing the same power source or in nearby electronics?

Here are my specific questions:
Q1: I want to power my electronics (BeeLine + PerfectFlite altimeter) using a single 9v power source. I suspect that some high frequency RF could leak from the BeeLine over the power wires to the PerfectFlite and mess up the PerfectFlite. Has anyone tried this? Did it work or did you see interference? [BTW, the reason I'm doing this is that I only have room for a single power switch which I can only get in a SPST version.]

Q2: My BeeLine came with the antenna pointing away from the circuit board as shown below in the photo with the yellow antenna. I'm trying to save room in my payload bay and would like to reorient the antenna so it lies alongside the circuit board (as shown in the photo with the red antenna below.) Do any of you fly this way? Has the BeeLine been reliable in this configuration? I'm concerned that induced RF might cause a problem for some of the BeeLine's own ICs.

My data point: I have mounted a BeeLine adjacent to a PerfectFlite in the past. The antenna was parallel to and about 10mm away from the PerfectFlite. I haven't had any reliability problems, though on one flight the PF did log some minor, periodic altitude increases that seemed to be correlated with the BL's transmittions.

Thanks,

Jim

Q1: The Beeline is designed to be powered from a 4.2V single cell. Greg would have to chime in for the definitive answer, but I believe a 9V battery would damage the unit. There may be a happy medium in voltage, but you'd have to contact both ends of the interface to know.

Q2: I have flown the Beeline with the antenna laying back across the board, and while it doesn't damage the unit, the range is reduced noticeably.

I do almost all of my flights using a Parrot altimeter adjacent to the Beeline, with the Parrot using its own small on-board battery, and a second tiny Li-poly shared by the Beeline and the Parrots deployments. The two units can fit within a 24mm coupler this way. The Parrot turns on the Beeline after apogee, using its 3rd output, to avoid any interference before then. I have found that when a Parrot has deployment charges hooked up to it (especially when the deployment charge wires are near the antenna), the charge wires can couple some noise into the baro measurement. The accel measurements are unaffected, and a Parrot without deployment charges hooked up is unaffected.

Thanks for the info. The BeeLine is actually spec'd to run with anywhere from 3.2v to 14v.

I like the idea of powering the BeeLine from the altimeter. Might as well not waste the battery until launch. Of course, it adds one more thing that can go wrong and prevent the transmitter from working. Given that I fly in New England, the transmitter is often my most important piece of electronics.

Do you power the deployment using a standard 3.7v LiPo? I would've thought that voltage was too low for reliable ignition.

I don't know how you managed to fit your BeeLine into a 24mm tube. A 29mm is the best I've been able to do since my BeeLine's circuit board is a full inch wide.

I would really like to try the Parrot someday. Ever since my PicoAlt AA2 was lost, I've been bemoaning the lack of an accelerometer on my altimeter. Baro-powered apogee detection doesn't seem nearly as accurate. One thing I wish the Parrot had was a big 'ole capacitor for powering the ejection charges. I generally use the Newton's 3rd ejection canisters which don't require a license to buy but I do think require a little more current than a typical e-match. For smaller airframes, I like to use A10 batteries which need the boost a capacitor provides. Any plans to offer that as an option? Is there a list somewhere of which igniters/e-matches are supported by the Parrot?

Jim

jcsalem said:

Thanks for the info. The BeeLine is actually spec'd to run with anywhere from 3.2v to 14v.

Click to expand...

Are you sure about that? This is from the documentation:

"The BeeLine Transmitter is designed to operate off of a single cell lithium polymer battery. Other battery sources may be used, but the MAXIMUM BATTERY VOLTAGE MUST BE LESS THAN 6.6 volts, otherwise damage to the on-board processor may result. By changing or removing components on the board, it is possible to use higher voltage levels including a standard, 9V alkaline battery."

Of course you may be planning to make those changes of components. Is that the idea?

https://bigredbee.com/docs/beeline/BeeLineDoc.pdf

The BeeLine Transmitter cannot be run from a 9V, but the BeeLine GPS can.

Is it possible some are discussing the GPS, and others the standard tracker?

-Kevin

jcsalem said:

Thanks for the info. The BeeLine is actually spec'd to run with anywhere from 3.2v to 14v.

I like the idea of powering the BeeLine from the altimeter. Might as well not waste the battery until launch. Of course, it adds one more thing that can go wrong and prevent the transmitter from working. Given that I fly in New England, the transmitter is often my most important piece of electronics.

Do you power the deployment using a standard 3.7v LiPo? I would've thought that voltage was too low for reliable ignition.

Click to expand...

Yes, a tiny 65 mAhr cell, which only weighs about a gram. Its internal resistance is really low, despite its small size (much lower than any similar-sized capacitor), so it has no problem putting about 3 amps through the Estes ignitors I use for my deployments. I pot the ignitors with epoxy into little pyrodex-filled cardboard launch lugs. No LEUP hassle. This battery also works well with the new Quest ignitors. For a high-resistance ignitor, a higher voltage source is required.

jcsalem said:

I don't know how you managed to fit your BeeLine into a 24mm tube. A 29mm is the best I've been able to do since my BeeLine's circuit board is a full inch wide.

Click to expand...

Belt sander. The most under-rated rocketry tool in my workshop. I also trimmed the programming connector so that a Parrot could fit side-by-side next to it inside the 24mm coupler.

jcsalem said:

I would really like to try the Parrot someday. Ever since my PicoAlt AA2 was lost, I've been bemoaning the lack of an accelerometer on my altimeter. Baro-powered apogee detection doesn't seem nearly as accurate. One thing I wish the Parrot had was a big 'ole capacitor for powering the ejection charges. I generally use the Newton's 3rd ejection canisters which don't require a license to buy but I do think require a little more current than a typical e-match. For smaller airframes, I like to use A10 batteries which need the boost a capacitor provides. Any plans to offer that as an option? Is there a list somewhere of which igniters/e-matches are supported by the Parrot?
Jim

Click to expand...

The Parrot can handle 4 Amps for 1 second, so that covers all ignitors and ematches that are out there, as far as I know. You just have to match the deployment battery to the ignitor you're planning to use. A 9V battery is inefficient size-wise, and it has high internal resistance, but it works for pretty much any ignitor or ematch, since it limits its own current to 4A.

Thanks for all the feedback.

As far as the voltage, I was taking the 3.7v to 14v range from the BeeLine FAQ here: https://bigredbee.com/forums/viewtopic.php?t=19

However, I'll believe the more recent doc. Looks like Greg needs to update the FAQ!

Thanks for saving me from having the BeeLine go up in smoke!

Jim

jcsalem said:

Thanks for all the feedback.

As far as the voltage, I was taking the 3.7v to 14v range from the BeeLine FAQ here: https://bigredbee.com/forums/viewtopic.php?t=19

However, I'll believe the more recent doc. Looks like Greg needs to update the FAQ!

Thanks for saving me from having the BeeLine go up in smoke!

Jim

Click to expand...

This was another post concerning the FAQ in 2005.

Question:

"the FAQ says you can use a battery from x volts all the way up to 14v. is this true? does the power output increase with the higher battery pack?" kc9esf

Answer:

"Yes, any input voltage can be used as long as the max regulator power dissipation is not exceeded. This input V is immediately regulated down to 3.0V, so no increase in power w/ an increase in battery. Maximum voltage is 12-14V.

Just be careful if you increase the voltage input to more than 6 volts, there's a resistor divider that needs to be modified/removed to avoid damaging the PIC if you want to run higher (like 9 or 12V)."

https://bigredbee.com/forums/viewtopic.php?t=16

Better off reading the manual than the FAQ which clearly lacks the detail of the manual.

Bob