cyamamot@castor.usc.edu (Cliff Yamamoto) (04/13/89)
Greetings!
Can someone recommend I manufacturer of dummy speaker loads? I don't
feel like soldering dozens of wire-wound resistor together on a huge heat sink.
Something like a 50 Watt, 4 or 8 ohm load would be preferable. The last time
I saw a dummy load was in a stereo repair shop, but they were using a single
50 Watt wire-wound from Dale the size of a spray can!
The reason for the load is I'm installing a removable sub-woofer in the
car and when it's not in there, I've been told the amp should have a dummy
load even if when little or signal is coming through. Is this true?
Thanks in advance
Cliff Yamamoto
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Internet: cyamamot@castor.usc.edu castor!cyamamot@oberon.usc.edu
cyamamot@nunki.usc.edu cyamamot%nunki.usc.edu@oberon.usc.educook@stout.ucar.edu (Forrest Cook) (04/18/89)
In article <3474@nunki.usc.edu> cyamamot@castor.usc.edu (Cliff Yamamoto) writes: > Can someone recommend I manufacturer of dummy speaker loads? ... > The reason for the load is I'm installing a removable sub-woofer in the >car and when it's not in there, I've been told the amp should have a dummy >load even if when little or signal is coming through. Is this true? Remember, you are dealing with stereo salesmen here. A friend of mine once said that salesmen are one step below child molesters :-) (That's a JOKE, Don't take it seriously, save net bandwidth, etc.....) It would be much more efficient if you just installed a power switch on the sub woofer's amp for removing power when the speaker is not installed. How about making an assembly with the amp and woofer in the same box that can be removed at the same time. ^ ^ Forrest Cook - Beware of programmers who carry screwdrivers - LB /|\ /|\ cook@stout.ucar.edu (The preceeding was all my OPINION) /|\ /|\ {husc6|rutgers|ames|gatech}!ncar!stout!cook /|\ /|\ {uunet|ucbvax|allegra|cbosgd}!nbires!ncar!stout!cook
monty@sagpd1.UUCP (Monty Saine) (04/18/89)
> > Can someone recommend I manufacturer of dummy speaker loads? I don't >feel like soldering dozens of wire-wound resistor together on a huge heat sink. >Something like a 50 Watt, 4 or 8 ohm load would be preferable. The last time >I saw a dummy load was in a stereo repair shop, but they were using a single >50 Watt wire-wound from Dale the size of a spray can! Back in my high school days we used regular incandescent light bulbs for loads. Don't know if that would be pratical in this case, but theey do make for a cheap high power load. For what its worth??? Monty > >Thanks in advance >Cliff Yamamoto
rrw@naucse.UUCP (Robert Wier) (04/19/89)
Regarding audio dummy loads... I once used (many years ago) a light bulb to tune up my amateur radio transmitter. Kind of neat to see the light flash in synch with your voice on SSB. However, it's not recommended because 1) the load is complex (lots of inductance), 2) the resistance of the filament changes as it heats up and cools down and 3) it radiates (leaks) rf. I once made a 500+ mile contact on a 50 watt light bulb (ahem...) Heathkit sells a "Cantenna" which is basically a one gallon paint can with a 50ohm resistor suspended inside. The idea is that you fill it with mineral or transformer oil which will circulate and dissapate any heat. Its rated up to 1,000 watts up to a frequency of 450 Mhz. I would suppose you'd want something in the range of 4-12 ohms for audio work. I note that in the Newark catalog they have Dale high wattage resistors. You could parallel, say, 5 20W 100 ohm values and come out with something usable. If you stick 'em into a cantenna, the rating would be considerable higher... - Bob Wier College of Engineering Flagstaff, Arizona Northern Arizona University ...arizona!naucse!rrw | BITNET: WIER@NAUVAX | *usual disclaimers*