Sporty's PJ2 PIREP and nordo while in class Bravo

nj-pilot

nj-pilot

Pre-takeoff checklist
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Display name:
josh_me
Good learning experience today - will keep this post brief:
  • Flying Hudson corridor north at 1500 with ATC
  • In a C172SP with G1000 (rental)
  • Right around the GWB (talking to La Guardia tower), MFD and PFD go dark - all avionics still functioning, but cannot see or control comms (or anything other than the standby flight instruments)
  • I advise ATC that I won't be able to switch frequencies until I work it out
  • Tried pulling/resetting fuses and switches, tried the MFD backup button - nothing worked
  • Home airport is KCDW - which is ~15 mi to the west (class D under the B shelf)
  • I pull out my Sporty's PJ2 radio, connect it to the USB power source, plug my headset in - and tried to confirm with ATC that they could hear me
  • Radio malfunction: With headset plugged in, every time I use the PTT button to talk, it would disconnect transmission (but I could hear them just fine)
  • Tried without headset plugged in, worked a little better, but still cut my transmission in and out (and it was hard as hell to hear them without my headset)
  • Unsuccessful in my attempts, the super helpful controller at La Guardia tower was kind and supportive enough to allow me to stay on his frequency as he cleared me back to KCDW (and cleared me to land)
Lesson learned: If you have a backup radio, TEST IT OUT. I should have tested it as part of my pre-flight (from now on I always will).

Regarding the PJ2, it's out of warranty, but I'm pretty annoyed that it operated so poorly. I'm going to write to Sporty's and see if they'll replace it or repair it. Otherwise, welcome any suggestions for backup radios - I now know for sure that I need my backup radio to have headset adapter/plugs and an optional wired power source (i.e., if I don't have enough battery power).
 
My experience with the PJ2 is that in an airplane like the 172 surrounded by the aluminum airframe acting as a Faraday shield, much of your transmitter's output power is reflected and results in a high SWR. This high SWR is likely the reason your transmitter cuts out; the PJ2 has protection so your RF output transistor isn't damaged by the high SWR. You really need a quick way to connect the PJ2 to an external antenna permanently mounted on the airframe. The PJ2's rubber duck antenna is basically useless while you're airborne unless you're within a very few miles of the ground station you're trying to talk to. Since you were in a rental, connecting the PJ2 to an external antenna is a problem.

I've had much better luck using the PJ2 rubber duck in my Zodiac which has a bubble plexiglass canopy (SWR isn't a problem), but to increase my transmission range I plan to permanently install a female BNC coax connector on my instrument panel connected to a panel mounted coax switch so I can switch my external com antenna to either my panel mounted com transceiver or the panel BNC connector, and use 3 ft long RG-400 coax cable with male BNC connectors on both ends to connect the PJ2 female BNC antenna connector to the female panel mounted BNC connecter.
 
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I've got a yaesu 550 and have similar experiences. Could hear tower, but transmitting was pretty poor. It worked, kind of. But I'll still squawk 7600
 
1. You need an external antenna with a good BNC connection.
2. The radio requires at least 3.1 amp power to get the TX circuit active.

The radio is telling you that it lacks amps to power up the TX circuit. It is probably fine, but you need
the amps to power up TX. RX requires much less from the radio.

I've got one too and I sent it back to be checked and it was fine. They suggested a different battery for the USB
and with a new BNC connector to my external antenna that fixed it. The previous battery couldn't power the
TX even though it spec'd as the same amperature. Works fine now. Its seldom the
radio.
 
I've hit a field ten miles out with my handheld. Was a while ago, but it worked.
 
nj-pilot said:
Good learning experience today - will keep this post brief:
  • Flying Hudson corridor north at 1500 with ATC
  • In a C172SP with G1000 (rental)
  • Right around the GWB (talking to La Guardia tower), MFD and PFD go dark - all avionics still functioning, but cannot see or control comms (or anything other than the standby flight instruments)
  • I advise ATC that I won't be able to switch frequencies until I work it out
  • Tried pulling/resetting fuses and switches, tried the MFD backup button - nothing worked
  • Home airport is KCDW - which is ~15 mi to the west (class D under the B shelf)
  • I pull out my Sporty's PJ2 radio, connect it to the USB power source, plug my headset in - and tried to confirm with ATC that they could hear me
  • Radio malfunction: With headset plugged in, every time I use the PTT button to talk, it would disconnect transmission (but I could hear them just fine)
  • Tried without headset plugged in, worked a little better, but still cut my transmission in and out (and it was hard as hell to hear them without my headset)
  • Unsuccessful in my attempts, the super helpful controller at La Guardia tower was kind and supportive enough to allow me to stay on his frequency as he cleared me back to KCDW (and cleared me to land)
Lesson learned: If you have a backup radio, TEST IT OUT. I should have tested it as part of my pre-flight (from now on I always will).

Regarding the PJ2, it's out of warranty, but I'm pretty annoyed that it operated so poorly. I'm going to write to Sporty's and see if they'll replace it or repair it. Otherwise, welcome any suggestions for backup radios - I now know for sure that I need my backup radio to have headset adapter/plugs and an optional wired power source (i.e., if I don't have enough battery power).
Click to expand...

Sportys has been great repairing my Bose headsets and my SP400 hand held radio. The radio was 2 months past the 5 year warranty and they repaired it for no cost. Took 2 days. I fly over there and drop off and pick up.
 
skyking3286 said:
1. You need an external antenna with a good BNC connection.
Click to expand...

I would add that the BNC connector needs to be CLEAN. I've seen more than a few airplanes with external antenna connectors that are all corroded to heck because they don't get used. They need to be cleaned up to be useful.
 
skyking3286 said:
2. The radio requires at least 3.1 amp power to get the TX circuit active.
Click to expand...
I'm curious where you found that spec. The PJ2 manual specs transmitter power consumption at 1 Amp maximum, although it doesn't specify whether that's at USB voltage (5 volts) or 12 volts.
PJ2 Specifications.jpg
 
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steingar said:
I've hit a field ten miles out with my handheld. Was a while ago, but it worked.
Click to expand...

My experience was similar with a Vertex 300 radio using the rubber duck and the headset adapter (with a monaural headset). Lost communication with local Unicom 11 nm out while flying away at 3000 ft from the airport (so maximum metal between my radio and the receiver). A Tiger does have a fair amount of window area, though, so behavior in less open cabin may be poorer.

Connecting the handheld radio to the bottom external antenna about doubled the range.
 
That spec comes from experience. I had a 2.1 amp battery power bank that matched the Sporty's specs for the radio and
it didn't have the amps to power the TX. I found out by listening to LiveATC and the fact they didn't pick up the TX even though
people close by could hear. I sent it back and it checked out perfectly. The 3.1 amp one they sell ( Flight Gear Backup Battery for iPad 10,000 mAh) works just fine with it now.
Not every battery bank that has 2.1 amp on the specs can power it, but the newer ones are rated at 3.1 amps and they are recommended by Sporty's. So I wouldn't fool with 2.1 amp, but go with a 3.1 amp that can be continuous with that output.
 
I use either the alkaline battery pack or have the Flight Gear 10,000 mAh "Quick Charge 3.0" p/n 2837A battery pack plugged into the PJ2 and have never had a problem getting the full rated 1.5 watts PEP output into a 50 ohm dummy load measured with a VHF RF wattmeter.
 
Update: Sportys evaluated my radio and agreed to send me a replacement radio - they are the best! They confirmed that even with just USB power alone (i.e., no batteries), the radio will have sufficient power to transmit.
 
I have two radios on separate systems on my plane but my backup radio is my cellphone. Just connect the Bluetooth to the bose and call whoever you need.
 
Derald Madson said:
I have two radios on separate systems on my plane but my backup radio is my cellphone. Just connect the Bluetooth to the bose and call whoever you need.
Click to expand...
That's great if you know the phone number of the tower, approach, or center you need to talk to and they're not too busy to answer the phone.
 
Stan Cooper said:
That's great if you know the phone number of the tower, approach, or center you need to talk to and they're not too busy to answer the phone.
Click to expand...
I might also worry about cell reception, unless you're at a low enough altitude
 
Stan Cooper said:
That's great if you know the phone number of the tower, approach, or center you need to talk to and they're not too busy to answer the phone.
Click to expand...
I'm not 100% sure this is still accurate, but it's worked for me in the past - a good PDF to add to your ForeFlight documents (or however people like to access docs)
 
On other fact is with handheld radios, you don't want to TX without an antenna attached. It can do bad things to the radio. I use USB without a battery pack on mine.
 
I carry an Icom IC-A14. I like that the lithium battery will hold a charge for many weeks.

I've never used mine to talk to ATC, but have routinely used it to talk to other aircraft in the pattern at uncontrolled fields. Works great for that, with the little rubber duck antenna and the headset adapter.

If I had a plane, I'd probably put a separate antenna on it, either an official aircraft vhf antenna, or an nmo mount, and run a bnc jack to under the dash, rather than splice into one of the radio's cables.
 
What type of antenna are you guys using to connect to handheld.
Dedicated to just handheld.
 
I arrived IAD one night with only a receiver once. ATC heard one transmission from us but did some turns to identify us and determine our intentions.

I've also prearranged a NORDO departure from IAD (sort of). I had the radio while flight of two-ing a NORDO Queen Air out. That one was even after 9/11.
 
I picked up a clever USB voltage and ammeter for $3.00 (!) at the ARRL Pacificon convention last weekend, and hooked it up between the PJ2 USB power adapter and the PJ2 USB port just to check the current draw in receive and keying the push-to-talk for transmit. I removed the battery pack, so the USB port was the only source of power.

I had a 50 ohm dummy load on the antenna BNC connector. USB voltage was constant at 5.01 VDC. In receive (squelched) current draw was 0.11 amps. When I pressed the PTT and transmitted, current draw was 1.20 amps, and whistling into the mike to modulate the carrier, the current remained at 1.2 amps.

PJ2 USB Volts 5.01V.jpg PJ2 USB Amps Rcv 0.11A.jpg PJ2 USB Amps Tx 1.20A.jpg
 
nj-pilot said:
  • Right around the GWB (talking to La Guardia tower), MFD and PFD go dark
Click to expand...
Lots of comments about the radio, but none about the G1000 going dark. Did anyone figure out what happened there?
 
azpilot said:
Lots of comments about the radio, but none about the G1000 going dark. Did anyone figure out what happened there?
Click to expand...
Yes - I'm told the G1000 was set to auto-dim the screens based on ambient lighting (e.g., dimmer when it's nighttime). This is a setting I was unaware of.

Anyway, two malfunctions:
  1. The ambient light sensor incorrectly thought it was nighttime, and set the screens dark
  2. The level of dark it auto-selected was practically black - when I pulled the switch to reset it, couldn't even tell the difference - screens were black in both cases
 
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