Show us the status of your RV-4 project! - Page 42

Larry DeCamp · #**411** 02-17-2022, 05:24 AM

I had bad transmission clarity from the start and weak headset performance with the in ear Halo QT. Fiddling with all the setting options on the radio made little difference. So, I finally deployed the simple setting option ie., not messing with all the bells and options the designer can optimize. Your experience is not unique and there are numerous posts here with good advice on set up, but I Ended up with basic simple ( dont remember the term in the instructions) and it worked very well. I also switched to Bose A20 and the radio sounds like a 747 Captain landing at JFK .

acroboy · #**412** 02-20-2022, 10:14 PM

Quote:

Originally Posted by Larry DeCamp

I had bad transmission clarity from the start and weak headset performance with the in ear Halo QT. Fiddling with all the setting options on the radio made little difference. So, I finally deployed the simple setting option ie., not messing with all the bells and options the designer can optimize. Your experience is not unique and there are numerous posts here with good advice on set up, but I Ended up with basic simple ( dont remember the term in the instructions) and it worked very well. I also switched to Bose A20 and the radio sounds like a 747 Captain landing at JFK .

Yes, I've already played with many settings and have flown with two very different headsets. I've tried with VOGAD and VOX OFF, and various microphone settings. I'm sure there is a pony under there somewhere. I heard of similar symptoms from mic grounding as well. Hopefully i will find it this week

acroboy · #**413** 03-04-2022, 10:18 PM

After reinstalling the radio it now transmits at full volume. Sounds great without the engine running but transmit becomes somewhat garbled when in flight and noisy. Much better over all. Gonna play with settings more.

I changed my baffles to have proper taper for my ECI cylinders, added the duct/channel on the back of #3 , an air dam on #1, and plugged all of the little holes. Today on take off I still had 415F on two cylinders at 120 kt climb and 75F ambient. Had to substantially reduce power to control. Before hot to cold was 3,4,2,1. Today was 1,4,2,3. Obviously the #3 duct worked great and #1 air dam was too much. Conditions were warmer and lower altitude so hard to compare Temps to previous flights but guessing I'm about 10 F cooler at cruise on average. Assuming I reduce the air dam size I think that leaves me with #4 a problem during climb only. #4 is middle of the group in cruise.

I've traced my heavy wing to an improperly fabricated outer wing aileron bracket on the left side. I've got to make a new one, there isn't enough room to simply adjust the aileron bracket. A bummer but shouldn't be too difficult.

acroboy · #**414** 03-06-2022, 10:01 PM

I removed #1 air dam and had best cooling experience yet. 120kt climb, 85F ambient #4 got to 410F but I didn't have to pull power back for the first time ever. All others remained less than 400. Once cruising at 3000ft, 2500 RPM, all cylinders were about 350F and within 10 degrees of each other. I'm going to try taping off the top 25% of the oil cooler to see if that helps #4 climb temperatures without hurting oil temperature. I'm excited to think I am close to solving my cooling problems.

acroboy · #**415** 04-30-2022, 05:55 PM

I thought I would provide an update. The plane now has 45 hours and is out of Phase 1. The last two flight have included my son as passenger which was super fun. He helped buck many of the fuselage rivets years ago.

Today I proved the radio was finally fixed and that was the final squawk! I had discovered the radio transmission was good at frequencies 121.0 and above and quickly degraded as the tuned frequency was reduced below that. I finally pulled the antenna and measured the VSWR and I couldn't get a stable reading. Sometimes it was in spec but the slightest movement made the reading swing wildly. I inspected the antenna and discovered it was cracked at the bend (see pics). I ordered a RAMI replacement and today I sounded like a boss (and the tower agreed)!. I bet if I ground down the crack and soldered the crack the old antenna would work too. It is such a relief to finally have that solved. I thought the varying performance vs frequency was a very odd symptom. I hope my experience might help someone else with their radio. I'm sure I cracked the antenna during the build. I remember more than once running into it while on the mechanics creeper. The old antenna was a Delta Pop Red-Tip. I purchased the RAMI on the outside chance it had something to do with the Delta Pop and my radio. I am now very happy with the MGL V6 radio.

[quote=acroboy;1593748]After reinstalling the radio it now transmits at full volume. Sounds great without the engine running but transmit becomes somewhat garbled when in flight and noisy. Much better over all. Gonna play with settings more.