L-Per Issue

[Corporal Punishment]

So, I built an L-Per from parts a few months back and I have been having some issues recently.
When I first got the receiver, the needle would usually stick to the left when I was using it so you would have to give it a little tap to get it unstuck. Since then, I have changed the crystals to aircraft frequencies, and I have built the antenna. Recently I have been having issues with the needle not going to the left at all and it only staying in the center in REC unless I get a strong enough signal to move it to the right. When I let it sit for a few hours or days and I test it again it is fine but after a little bit of use the same problem happens again. Here is a video of when I first got it: https://youtube.com/shorts/vogAi_K9jfY?feature=share
Here is a video of it now:
https://youtube.com/shorts/rYNwGg-tyhw?feature=share

Does anybody know of any solutions to the issues I am having?

[SarDragon]

Have you gone through a complete alignment for the aviation frequencies? It's a narrow tuned receiver, so if the alignment is off, it won't work right.

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[Corporal Punishment]

I do not believe so, how can I go through a complete alignment for aviation frequencies?

[SarDragon]

The manual has a complete alignment procedure. You will need a signal generator,  o'scope, and appropriate voltmeter.

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[Corporal Punishment]

Amazing, I have none of those. I'll call someone I know to see if I can find someone who does.
Thank you for the help by the way.

[radioguy]

You might be able to talk a local 2-way radio shop into checking the alignment for you.  They have the necessary tools.

[SarDragon]

But do they have a manual? I no longer have mine, but I have thoroughly read it, and the alignment procedure is specific and detailed. It requires someone with experience in performing such. Getting inside the box and changing the adjustments willy-nilly will likely brick the unit.

[Corporal Punishment]

You might be able to talk a local 2-way radio shop into checking the alignment for you.  They have the necessary tools.

I might talk to my unit commander about it, he does some stuff with amateur radio so he might be able to help me out. I currently have the manual and found the info, so I just need to find someone with the proper equipment.

[JayCraswell]

I've always hated that follow the needle mode. Even if it works (Which is rare in what I've observed) you never know if you going to the target or 180 degrees away from it.  All you really get from that mode is knowing your on the beam and the antennas need to be unbent up and how many LPERs have straight antennas?

I borrowed the design for a 3 element Yagi made from PVC and cut up chunks of measuring tape (Spring steel) I used YagiCad and scaled it from 145 (Ham Band) to 121.5MHz.  Then I just use recv mode. The Yagi hears weaker signals is very accurate (gives you a good cut / azmuth) and because its spring steel you can crash around the woods and brush (getting it all bent) and all you do it give it a flick and it goes back to the way it was.

Other then never using anything but recv mode I would make one last suggestion that our Capt Roedder gave me. Forget the meter totally. Put the elper up to your ear and turn down sensitivity until you can just hear the signal and in only one direction. Signals bouncing off hangers will be weaker so you won't be easily fooled following reflections. He explained that the dynamic range of human hearing is far better then anything electronic (Meters or lights)  And for the last three real ELT missions I tried this and I've become a firm believer that he is correct. I teach it this way as well and try to get everyone to only use recv mode. The other way seems like a nice trick but... Its just not that great.