My friend Rich K0ZX has been using his NanoVNA (original type) outdoors, and asked me about options for improving display visibility. I went searching for possible solutions and ran into a low-cost camera viewfinder accessory (some digital cameras also have ~2.8" LCD display, and are subject to the same visibility impairments when used outdoors.)
A few weeks ago I ordered on ebay the 2.8" LCD viewfinder listed below (now about USD 12; they seem common on ebay and I'm sure there are alternatives to consider...)
It arrived after about a month, and after popping out (inverting) the rubber material eye cup (it's shipped in a backwards configuration reduce size of shipping container) and placing it on my (very much original-era NanoVNA), it does indeed somewhat magnify the display and shield it from ambient light.
A few of caveats:
1. The touchscreen is obviously not accessible while the viewfinder is in place, and my nanovna is pure original vintage, no updates, so the manual button/switch controls leave more than a little to be desired;
2. The focus isn't quite perfect - it seems that it the small gap between the LCD plane and the viewfinder focus point caused by the PC board material takes the viewfinder slightly out of focus, but it's still quite readable, nonetheless;
3. There's no immediately obvious way to fix the viewfinder to the NanoVNA.
In any event, I wanted to pass this along to our user hhcommunity to see if it inspires any further ideas.
A few photos are attached. Please excuse the up/down inverted photos (photography hasn't been my thing since about 1962!)
Comments and observations welcomed!
73 Dave WB0GAZ wb0gaz@...
