Main Question or Discussion Point
Does anyone know an online store that sells ECE tools for soldering/desoldering and other electronic components?... other than RadioShack.
Why complain you do get 4 or 5 resistors for that dollarManchot said:I can't stand shopping at RadioShack for components. "Hey everyone, let's pay a dollar for a 1 kOhm resistor!" I guess that's the price you pay for convenience.
I do appreciate the advantage of low temperature soldering. I am curious about this thermal heating with RF. Do you know at what frequency or power level, their RF is generated?berkeman said:Try www.jameco.com
For higher-end soldering tools, check out www.metcal.com
The Metcal irons are awesome. They use RF heating of the tip, so they warm up in less than 10 seconds, and they keep the tip temperature solid, whether you're soldering a TSSOP SMT package (tiny leads) or big 16AWG wires onto lugs. They're expensive, but worth it if you do a lot of soldering, especially SMT.
I started at Metcal.com and found that they call their technology SmartHeat. Then a quick Google search got me here to this interesting page:Ouabache said:I do appreciate the advantage of low temperature soldering. I am curious about this thermal heating with RF. Do you know at what frequency or power level, their RF is generated?
This system uses the Metcal SmartHeat technology. Which utilizes Skin Effect of a 13Mhz RF signal from a constant current power supply. This means the heat is generated on the surface of the tip delivering tremendous power when need at amazing accuracy. This design also means there is no internal thermo couple of heating element to fail as in other brands. Since this design uses skin effect in the tip cartridge to Generate the heat the physics of the system achieve a +/- 1.1 degree temperature stability and there is no calibration required. Tip cartridges swap easily without the use of tools.
The Metcal base unit drives the RF energy down a flexible coax to the coaxial tip. The only RF energy outside of the system would be leakage. The exposure standing in front of a 2.4GHz microwave oven cooking dinner is probably several orders of magnitude worse.Ouabache said:Thanks for the reference. So I wonder how much RF power is a user exposed to (at 13MHz), each time the trigger is depressed? ANSI and IEEE set some maximum safety limits for SAR (specific absorption rate) of 0.08 W/kg for whole body exposure and 1.6 W/kg for exposure of limbs in that frequency range.
This is fascinating technology, I would like to understand the design aspects. Lets see if I understand so far; the base unit transmits a 13MHz signal down the coax, concentrating its energy along the surface of the center conductor (skin effect), to the load (iron tip). By that description, it sounds like the iron behaves as a poorly tuned antenna. Instead of the RF radiating into space, it is converted to heat at the iron tip, and lots of signal reflected back to the source. This is a possible explanation for generating heat. If this were the case, how might they shield that much reflected RF. I wonder if there is something else going on.berkeman said:The Metcal base unit drives the RF energy down a flexible coax to the coaxial tip. The only RF energy outside of the system would be leakage. The exposure standing in front of a 2.4GHz microwave oven cooking dinner is probably several orders of magnitude worse.