Friday, October 14, 2016

FM notch filter

I'm not sure why I never shared this, but I completed the notch filter.  I had made it with the same board outline as the TINYLNA Rev A, so I had to cut out the tabs on either side to fit it down into the housing.  But I turned on sharing of the project on OSH Park.  Also, I have a schematic and layout I will share below.  OSH Park

Friday, April 8, 2016

Sharing on OSH Park

I've been very busy with work lately, so I haven't had enough time to work on my RF projects.  So I decided to at least share the board layout.  With the other information on this blog, it would be easy for anyone to build the board themselves.  So check out the OSH Park layout and order a few boards.  They're only like 80 cents each since they're so small.  Anyone who gets them going drop a comment.

Friday, January 29, 2016

Rev B boards are in

Just received the next revision TINYLNA boards with the slots for the housing pins.  This will allow me to drop the board straight down into the housing and solder it from the top.  The boards look good, but it appears the metal pads flake off a bit when the board outline is cut.  That's to be expected since they request the metal doesn't come to the edge of the board.  The board sits well into the housing, so the dimensions are all good.  I can use this board outline in the future for other functions (like the FM notch filter board).  Next is soldering components and soldering into the housing.

Monday, January 4, 2016

New installation

I had an idea for a new installation method.  I dremmeled slots where the housing pins are located and dropped the board straight down into the housing so it lies flat.

The board is flush to the bottom of the housing.  The board is held in place by the tab like a through hole component.  It's just the right height.  It's possible this is how the housing is intended to be used it works so well.

I will update my layout and do another board spin.  I'll also shrink the board dimensions just slightly to help it fit better.  In the meantime I'll try to come up with a quantitative way to measure its performance with the tools on hand.

Components on board

Got the components soldered onto the TinyLNA.  It's tough work with the tools at hand (no microscope, no solder paste).  I included the option to have the DC voltage shoot through towards the antenna, but did not solder it on this version.  I also did not solder on the ESD diodes for this version.

And then installing the board into the housing was even more difficult.  Getting the board to stay put while soldering was pretty tough.  Electric tape wouldn't hold it in just the right spot so I had to rely on fingers way too close to the iron tip.  I may have to come up with a different installation method.