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General Category => General Discussion => Topic started by: Downhome Upstate on April 06, 2013, 06:37:45 AM

Title: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: Downhome Upstate on April 06, 2013, 06:37:45 AM: >:( Oh, well. Anyone going to say 'welcome to the club'?
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: Paully on April 06, 2013, 06:50:02 AM: Welcome to the club, though I have to admit I haven't smoked one. I usually put the LEDs in backwards. Must be a nice Radio Shack, I can't remember the last RS I was near that had carbon comp resistors.
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: Grainger49 on April 06, 2013, 06:59:43 AM: I just broke about 4 in a row. They are delicate. If you call the Queen she will send you another first class mail. CC is the best here, carbon film is next.
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: Downhome Upstate on April 06, 2013, 09:15:27 AM: Quote from: Paully on April 06, 2013, 06:50:02 AM
Welcome to the club, though I have to admit I haven't smoked one. I usually put the LEDs in backwards. Must be a nice Radio Shack, I can't remember the last RS I was near that had carbon comp resistors.

Hey, Paully. Yeah, you're right. After 3 calls to different Rat Shack locations, I gave up. Decided to buy some stuff with the store credit I had with pcX, and threw the 220R 1/2 watt 5 percent'ers for the Seduction grid stoppers (like the one I smoked) in with the order. Gave me a chance to stock-up on quad-eutetic solder, solder wick, and make some shorting plugs while I'm at it.
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: Downhome Upstate on April 06, 2013, 09:18:13 AM: Quote from: Grainger49 on April 06, 2013, 06:59:43 AM
I just broke about 4 in a row. They are delicate. If you call the Queen she will send you another first class mail. CC is the best here, carbon film is next.

Hey there, Grainger. Yup. I was trying to un-solder one that was uncomfortably close to its neighbor when the body just kind of disintegrated. Had my soldering station on 700. Must have stayed just a wee bit too long.
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: earwaxxer on April 06, 2013, 10:01:43 AM: Because of my OCD I replaced the CC's with Tants. I do have some CC's waiting in the wings though, when I feel the need for a mod. From what I have read, the CC's have a nice 'tubie' sound to them. They are old school though, and not very reliable (that was the trip wire for my OCD).
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: Paully on April 06, 2013, 10:21:52 AM: All this talk of buying stuff from Partsconnexion is making me itch. I suddenly need to solder. Ok, what can I build that I really don't need?
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: Doc B. on April 06, 2013, 11:21:51 AM: Quote from: Paully on April 06, 2013, 10:21:52 AM
All this talk of buying stuff from Partsconnexion is making me itch. I suddenly need to solder. Ok, what can I build that I really don't need?

My vote - think I'll put one of these in my A-80:

http://www.ebay.com/itm/Nixie-Bargraph-IN-9-Stereo-VU-Meter-Fully-complete-kit-/270989833877 (http://www.ebay.com/itm/Nixie-Bargraph-IN-9-Stereo-VU-Meter-Fully-complete-kit-/270989833877)
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: Grainger49 on April 06, 2013, 11:40:22 AM: OOoooooo, Ooo, Ooo, Ooo! I may have to buy one of those! Thanks for the link! (sad when an engineer is so easily amused?)
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: Downhome Upstate on April 06, 2013, 05:22:33 PM: Definitely fits the bill !! 8)
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: Paul Joppa on April 08, 2013, 06:01:12 PM: Welcome to the club, I've smoked several. Metal films are a good substitute, and I see no reason to reject carbon film either. I expect we will make the switch eventually.

Traditionally, the bulk resistance of carbon composite has been assumed to be best because it has no inductance beyond that of its length. (Film resistors usually have a small spiral of conductive material which has a bit of inductance.) But VoltSecond, a long term Bottlehead who doesn't post much these days but is an excellent EE with tons of relevant professional experience, reports that he's used metal films as gate stoppers on extremely high transconductance FETs with great success. That's good enough for me - the real world trumps even the best theory, every time.
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: rock4016 on April 11, 2013, 03:48:09 AM: I've heard radio broadcasts come through an amp from using metal films as grid stoppers on high transconductance tubes, so it would depend on where the amp is used.
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: Paul Joppa on April 11, 2013, 10:29:29 AM: Wow - thanks for posting - it's always good to get more data! Much appreciated.
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: rock4016 on April 12, 2013, 02:16:04 AM: I wish I could give more details, but I didn't build the amp. I also know that Decware uses or used to use metal films(Dale/Vishay) as grid stoppers for the 6DJ8, which I would put in the high or higher than average gm catagory. So we may be talking about "certain" brands of metal films on "certain" tubes, like a 6C45pi 8)
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: coca on April 12, 2013, 03:55:44 AM: I have had a lot of good results in using mills non inductive wire wound resistors in that position as grid stoppers.

Bernie.
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: Grainger49 on April 12, 2013, 08:05:49 AM: It just hit me today... did smoking it get you high?

Sorry, sometimes I can't help myself.
Title: Re: Smoked my first carbon comp resistor w/soldering iron - Radio Shack, here I come
Post by: Downhome Upstate on April 13, 2013, 02:11:34 AM: Quote from: Grainger49 on April 12, 2013, 08:05:49 AM
It just hit me today... did smoking it get you high?

Sorry, sometimes I can't help myself.

Many years ago . . .