<!-- starting G4ZTD 2Par Calculator-->
var R1 = 0;
var R2 = 0;
var R = 0;
var R1M = 0;
var R2M = 0;
var RM = 0;
function clearBoxes(form)
{
form.R1.value = "";
form.R2.value = "";
form.R.value = "";
form.R1.focus();
}
function clearR1(form)
{
form.R1.value = "";
form.R1.focus();
}
function clearR2(form)
{
form.R2.value = "";
form.R2.focus();
}
function clearR(form)
{
form.R.value = "";
form.R.focus();
}
function solve(form)
{
var i = 3;
if(!form.R1.value) R1 = 0;
else R1 = eval(form.R1.value);
if(R1 == 0) i--;
if(!form.R2.value) R2 = 0; 
else R2 = eval(form.R2.value);
if(R2 == 0) i--;
if(!form.R.value) R = 0;
else R = eval(form.R.value);
if(R == 0) i--;
R1M = eval(form.R1M.value);
R2M = eval(form.R2M.value);
RM = eval(form.RM.value);
R1=R1*R1M;
R2=R2*R2M;
R=R*RM;
if(i == 0) return;
if(i == 1)
{
alert("\nMissing a value. Two values are required.\n");
return;
}
if(R1 == 0)
{
R1 = (R*R2)/(R2-R);
form.R1.value = R1/R1M;
form.R1.focus();
return; 
}
if(R2 == 0)
{ 
R2 = (R*R1)/(R1-R);
form.R2.value = R2/R2M;
form.R2.focus();
return;
}
R = (R1*R2)/(R1+R2);
form.R.value = R/RM;
form.R.focus();
return;
}
// end 2 Par Calculator -->


<!-- G4ZTD Multiple Parallel Resistor Calculator -->

<!-- start
var sigfig=5;
var R1=0;
var R2=0;
var R3=0;
var R4=0;
var R5=0;
var R6=0;
var R7=0;
var R8=0;
var R9=0;
var R10=0;
var R11=0;
var R12=0;
var R13=0;
var R14=0;
var R15=0;
var R16=0;
var R17=0;
var R18=0;
var R19=0;
var R20=0;
var total=0;
// end G4ZTD Multiple Parallel Resistor calculator -->


<!-- Clearing the box's -->

<!-- start
function clearboxes(boxes)
{
total=0;
document.boxes.r1.value=""
document.boxes.r2.value=""
document.boxes.r3.value=""
document.boxes.r4.value=""
document.boxes.r5.value=""
document.boxes.r6.value=""
document.boxes.r7.value=""
document.boxes.r8.value=""
document.boxes.r9.value=""
document.boxes.r10.value=""
document.boxes.r11.value=""
document.boxes.r12.value=""
document.boxes.r13.value=""
document.boxes.r14.value=""
document.boxes.r15.value=""
document.boxes.r16.value=""
document.boxes.r17.value=""
document.boxes.r18.value=""
document.boxes.r19.value=""
document.boxes.r20.value=""
document.answer.r21.value="";
R1=0;
R2=0;
R3=0;
R4=0;
R5=0;
R6=0;
R7=0;
R8=0;
R9=0;
R10=0;
R11=0;
R12=0;
R13=0;
R14=0;
R15=0;
R16=0;
R17=0;
R18=0;
R19=0;
R20=0;
}
// end Clearing the Boxs -->


<!-- Function Boxes -->

<!-- start
function calc(boxes)
{
if (document.boxes.r1.value!=""){R1=document.boxes.r1.value;R1=(1/R1)};
if (document.boxes.r2.value!=""){R2=document.boxes.r2.value;R2=(1/R2)};
if (document.boxes.r3.value!=""){R3=document.boxes.r3.value;R3=(1/R3)};
if (document.boxes.r4.value!=""){R4=document.boxes.r4.value;R4=(1/R4)};
if (document.boxes.r5.value!=""){R5=document.boxes.r5.value;R5=(1/R5)};
if (document.boxes.r6.value!=""){R6=document.boxes.r6.value;R6=(1/R6)};
if (document.boxes.r7.value!=""){R7=document.boxes.r7.value;R7=(1/R7)};
if (document.boxes.r8.value!=""){R8=document.boxes.r8.value;R8=(1/R8)};
if (document.boxes.r9.value!=""){R9=document.boxes.r9.value;R9=(1/R9)};
if (document.boxes.r10.value!=""){R10=document.boxes.r10.value;R10=(1/R10)};
if (document.boxes.r11.value!=""){R11=document.boxes.r11.value;R11=(1/R11)};
if (document.boxes.r12.value!=""){R12=document.boxes.r12.value;R12=(1/R12)};
if (document.boxes.r13.value!=""){R13=document.boxes.r13.value;R13=(1/R13)};
if (document.boxes.r14.value!=""){R14=document.boxes.r14.value;R14=(1/R14)};
if (document.boxes.r15.value!=""){R15=document.boxes.r15.value;R15=(1/R15)};
if (document.boxes.r16.value!=""){R16=document.boxes.r16.value;R16=(1/R16)};
if (document.boxes.r17.value!=""){R17=document.boxes.r17.value;R17=(1/R17)};
if (document.boxes.r18.value!=""){R18=document.boxes.r18.value;R18=(1/R18)};
if (document.boxes.r19.value!=""){R19=document.boxes.r19.value;R19=(1/R19)};
if (document.boxes.r20.value!=""){R20=document.boxes.r20.value;R20=(1/R20)};
total = R1+R2+R3+R4+R5+R6+R7+R8+R9+R10+R11+R12+R13+R14+R15+R16+R17+R18+R19+R20;
total = 1/total;
sigfig=eval((document.box.b9.value)-1);
if (sigfig>-1){
total=total.toExponential(sigfig);
if (total>.001 && total <1000){total=total*1}
}
document.answer.r21.value=" "+total;
total=0;
}