[Laser] A first look at RT5-2354DTS-C2 photodiodes

[Kerry Banke]

I received a lot of RT5-2354DTS-C2 photodiodes I purchased off Ebay and had 
a chance to take a quick look at them this weekend. They have a standard 
5mm clear molded plastic lens and short leads cut for PC mounting. The 
mounting of the diode inside the case is strange though. The diode is 
offset to one side so is not centered when looking in to the lens.  I put 
the diode in place of the SFH-203  in my receiver and saw about  a 7dB 
reduction in sensitivity to the 120 Hz signal from a light maybe 1/2 mile 
away.  I also just as a comparison pointed both the RT5 and the SFH-203 
bare diodes at the sun and measured the maximum current. The RT5 has about 
1/2 the output current of the SFH-203 which has 1/4  the area.  I need to 
confirm the optical beam width of the RT5 but believe it is 70 deg total. 
These are certainly functional for getting stared in optical communications 
but maybe not as good as the some of the other diodes mentioned that I 
and  others are using.  If anyone wants to run some tests on these, I'll be 
happy to send some off.
  - Kerry N6IZW -