RS 5b-Help repairing an EMIT tweeter

I picked up a set of RS 5b's yesterday for $80. The cabinets are in excellent shape (that is no dings, they will need a light sanding and tung oil) The woofers have been replaced with some real junk 10" woofers, but those can be replaced with the proper ones when they come available. My current issue is a non-functioning tweeter. I swapped them out, so I know it is not the internal wiring. From reading, I decided to open it up and take a look (that's what happens when good folks like you all give us a little insight :yes

It looks really clean and unmolested. What I am struggling to figure out is HOW the current runs through them. I measured them and the reading is upwards of 12 ohms. The spades seem to be rather intact with little to no wiggle.

Any insight would be most helpful.

P.S.I am also on the hunt for the woofers. I believe the part number for them is 902-5079.

Ya see dem two lil spots o' solder? Dem ones right chere ta the bottom of yer third pic'ure? Dey done gone bad on ya! Jes hit 'em up wit a hot iron, a lil one now, 15 watts 'er so, jes 'nuff ta melt dat stuff! As soon as she melts down get yer iron outta der! Ya should good t' go!

Well hells bells. I will let you know how it turns out. Much appreciated.

Very cool, Chef. I didn't see any obvious breaks in the emit circuit lines, so I had no idea what could be wrong with those EMITs. Good call, hope you were right and the OP has a working set of EMITs to work with.

First run at it with no success. But in this household, we try try again. Will keep you posted!

OK. I am hoping 3rd time is a charm. When I meter across the poles for resistance now, I get no reading. Hmm.

Get a magnifier and look closely at the traces. Sometimes theres an obvious failure other times the trace has a small hair line crack. You can also check continuity in small sectoins to find the failure.
Jim

if its a broken trace don't you get a ridiculous high ohm number...?

so that must be the issue...

Bkphoto said:

if its a broken trace don't you get a ridiculous high ohm number...?

so that must be the issue...

Click to expand...

I would still look them over. The higher ohm reading could be from the trace shorting itself kind of making a short cut to the other side. They can also be checked for resistance before the solder dot and if it's high there then he would know its not the solder joint. If the op is buying new woofers he will need to put a new emit on the shopping list.

OK third time is a charm! Not sure my meter is worth the $5.00 it looks like it is worth. Chef was spot on with his recommendation! They sound good on the top and middle. Now to find some woofers to replace these nasty replacements. If anybody knows of anyone with 902-5079's that would be super. Also, would the 902-2279a's work just the same?

Thank you!

Glad to hear it! I'm just back from a couple of days at the hot springs and it seems to have cured my grizzled 1860's prospector syndrome!

It works about 75% of the time, (to fix EMITs, the prospector thing comes and goes) I've saved a few EMITs since my first pair of Qb's back in the seventies.

Did you add a little fresh solder? It can help OR it can make you hold the iron there too long and then all the solder just drips out the back! I learned this trick here at AudioKarma myself!

http://www.audiokarma.org/forums/showthread.php?t=65571

Final feedback. Well, the EMIT did not work and no matter how many times I tried to flow the points, they would not read. I bought a very nice used EMIT for $50. Replaced the junk replacement woofers with a set out of a donor set of Qb's. The sound is good, but a little light on the bass. I looked at the crossover configuration and they are not the same, so it makes sense that the driver would not be matched perfectly. That being said, they do sound good with the mid and high's dialed down to bring out the bass. I will continue to look for a set of the correct woofers to replace these, but for now, all is good. I have a set of Qb cabinets that are in outstanding shape. Complete with the midranges. I would prefer to pay it forward. If you are reading this, if you need a nice set of Qb cabinets and mids, or you know of someone, just PM me. I am not looking to sell them, but rather pass on the magic of Infinity.