welll most of all it depend on price

i want make one like solaris LED...... at hk u can buy the XLamp XR-E Q4 at USD 5 per/pcs. but the lens.... refector.... is another problem and the temp. control..... i read from solaris LED it use 52 and 42 degree refector.....

have you tried use CREE Xlamp-E Q4. i have 20 it have 100 lm and much cooler

i know the LM 6001 circuit but i have some question. i can find ph 4.0,7.0 and 10.0 but other ph value i dont have so how is the data map find? only by calc.?

dear mark i want make a ph contorller and a orp controller too.. i have a few question. can u give me the ph sense part circuit to me ar? can u tell me the mcu part ph sense data map ar? my email is dannytt@gmail.com or danny_tt@hotmail.com many many thx