The emitters from the RFX9400 are too weak to reach a remote TV-set (approx. 7 meters) so I want the signal to be amplified. I think Xantech has a solution but I'm not familiar with their products.

Anyone ideas to solve this?

Why not use the remote IR out ?

Remote IR is useless because the hardware is in the other room. I need some sort of blaster.

Xantech do have an IR Blaster part number 39020 that you might want to look at

[Link: xantech.com]

rwind,

The 39020 may be useful for you, but be sure to read through the manual before ordering the unit because you will also need to add an IR receiver. And, the IR receiver will need to be wired to the 39020.

While you are on the XANTECH site, check out other solutions. Each situation is unique. XANTECH and others provide a range of solutions. Since I am usually dealing with crowded, closed cabinets, the blasters don't work well for me.

I usually try to stretch the budget enough to include an RFX9400 or RFX9600 because this eliminates the need to aim the remote and hold the position long enough for all of the commands to be emitted. I deal with a lot of impulsive customers and convincing them to hold still for a few seconds can be a major challenge. [Some TV's require 8-10 seconds (or more) between PowerOn and InputSelect.]

Most IR emitters have a current limiting resistor buried in the head with the emitter. Try lowering the value of this (or removing it all together to see if that helps. It is normally about 100 ohms at 1/4 or 1/8 watt. Wattage does not matter only resistance.

I use xantech amplified connecting blocks. They can drive a multiheaded emitter over several hundred feet of wire.

Barry what you suggest can be dangerous, for the probe not the user.

The resistor is there to limit the current to the diode. If there is no such resistor, the diode will most likely burn itself at the first use if the hardware that controls it (RFX) doesn't have a current limiter on it's IR outputs.

It could work, but is generally not a good idea.

While this is indeed true, common sense does apply and if someone is not familiar with electrical characteristics such as current/amperage, then they should not be mucking with such things and should consider purchasing amplification equipment such as a xantech 791-44 amplified connecting block.

LOL. I can't wait for Barry's response.

It must be a while Barry since you took a IR bud apart, :) there are very few these days with resisters in, there are all constant current drivers so no resistore required.

In my experience this is the trouble. Today, when youngsters "hack" their routers (install new firmware), jailbreak their iPhones etc. the common sense of "dont tinker what you don't fully understand" doesn't apply any more. Of course I'm not talking about the original poster or Barry, just a general thought. :)


True, I can't see a resistor in the pronto IR, so I believe the RFX has some current limiting. If I'm not mistaken even the user's guide tells how many IR diodes you can wire in series, thus implying the feed current is limited.

Yes I am old and have not taken an IR emitter (or bought one) apart in quite a while.

In my experience all Devices that drive IR elitters have current limiting so as to protect against a dead short.

Lyndell, et al; I naturally assume that all posters have at least a masters degree in EE and a doctorate in Comp Sci. (;-)

I have the former but not the latter as I was short sighted (youthful). When I was teaching (10 year time span) I tought every course in the Computer Science Graduate curriculum at a major university where I was employed as an associate professor (Associates are not eligible for tenure) in the evening division. I should have enrolled myself in each of my courses (company would have paid), given myself an A, and I would have had all the course work done with a straight A average. Registrar never knows whose teaching what and Barry Gordon is not an uncommon name. Some of the things I was working on where I was employed in my day job would have made good Doctorial Thesis candidates if I could get permission to document them.

Oh Well we do get much smarter (or more devious) as we get older

et tu Barry?

Lyndell?

:-)

Luv ya man!!!!

P.S. I started attempting BS in EE with minor in Math and CS but ended with BS in CS with minor in Math. I got too tired of having head in Physics book. Too much theory and not enough practice. I guess I was just too young and stupid as well.

Anyway, been working with Electronics etc since I was 9 years old.

The former will be (I hope time will permit) achieved in about a year time, the latter is not for me :). So I'll keep from posting until then ;).

Don't You dare (Keep from posting that is) I said ..."I naturally assume..... With advanced age comes the right to assume!

for(i=0; i<100; i++) widget("Blackboard", "Classroom").label= "LYNDEL";

Physics is just a branch of applied math (I should hear a lot on that one) as is EE as it is just a branch of Physics.

P.S. When I took EE my favorite course was "Leyden Jar Construction"; on a more serious note my favorite professor was Richard (Dick) Hamming the director of Bell Labs at the time and the inventor of Hamming codes. He taught a course in advanced numerical methods for engineers that had 4 students in it, myself and 3 grad students going for their PhD's that were my undergrad instructors.

I'm another one of those individuals who has been fussing with electronics since the single digit years.

BluPhenix, The series LED count is limited by the drive voltage. For planning purposes assume that the forward drop of the LED is about 2 volts. This means that a series string of four LED's will require about 8 volts drive. Given any additional drops in the drive circuit, adding a fifth LED with a 12V supply, is not likely to work because the LED's will not turn on.

The emitter's built-in current limit resistor attempts to prevent or minimize the damage if an emitter is accidentally connected to a voltage source. LED's are relatively fragile in terms of reverse voltage. The series resistor will not offer protection against high reverse voltage. If they are not already incorporating a reverse voltage protection diode in the emitters, they should consider adding this feature.