Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Mike_J on April 12, 2021, 08:47:49 am
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I was contemplating the RG316 Teflon cable I put in my Bassman. It looks to be about awg not much. Found this two conductor Teflon cable I bought from a surplus store many years ago. Each conductor appears to be 22awg. Thinking about replacing the two RG316 cables with a single two conductor cable.
The RG316 is probably adequate for sending a guitar signal to the grid but the 22awg would leave no doubts. Additionally, if I have any issue with amp stability then replacing the wires going from the V3 plates to the PI and from the PI to the grids of the power tubes may not be a bad first step. Can't see where that would hurt much.
Any comments or suggestions would be appreciated.
Thanks
Mike
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The purpose of using RG 316 or 174, and many others for signal transmission is that they are shielded. These signal cables do not carry much current -- they carry (very small) voltage signals. As such, their need for large diameter conductors is just not a factor.
Our larger wires are designed to carry current. Frankly, we over-spec our wire gauges in this community. For example, AWG 22 is generally designed to carry 7 amps before it heats up significantly.
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The purpose of using RG 316 or 174, and many others for signal transmission is that they are shielded. These signal cables do not carry much current -- they carry (very small) voltage signals. As such, their need for large diameter conductors is just not a factor.
Our larger wires are designed to carry current. Frankly, we over-spec our wire gauges in this community. For example, AWG 22 is generally designed to carry 7 amps before it heats up significantly.
I am certainly not going to generate 7 amps of current even on my best day of guitar playing. However, a problem I have been having with the RG316 is it breaks at the juncture of the conductor (wire) and its insulation and has on two separate occasions when I moved the wire after it was installed. Probably part of the problem is I put too much solder on the wire. However, there is so little of it that it is hard not to do. it is certainly a factor in why I am looking for an alternate Teflon solution.
The cable I took a picture of is Teflon and is shielded and the best part is it is already paid for and I have a lot of it. Will try the sluckey method of wrapping a lower gauge wire around the shielding for a shield grounding mechanism to make sure that works but don't see why it wouldn't. Everything is either silver plated copper or Teflon. Another factor is on the 5f6a Bassman there are four wires that have to go from the input jack to the 68K resistor close to the tube grid. That provides too many ways for problems to occur as things are configured now. Trying to make this as bullet proof as I can.
Unfortunately I know I don't have the soldering skills many of you that were trained in it have. I must make allowances for that. Have to deal with reality.
Thanks
Mike
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I understand what you're saying.
Both RG 174 and 316 use copper plated steel as their inner conductor -- it is brittle, and easy to break. Pre-tinning just makes it worse.
Do you use flux on your connectors? A little bit can really help the solder flow quickly, easily and reduce the "blobs."
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I understand what you're saying.
Both RG 174 and 316 use copper plated steel as their inner conductor -- it is brittle, and easy to break. Pre-tinning just makes it worse.
Do you use flux on your connectors? A little bit can really help the solder flow quickly, easily and reduce the "blobs."
No I just rely on the flux inside the solder. If you have something you can recommend that would make soldering better I sure would appreciate knowing what it is.
Thanks
Mike
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I use a Kester 186 Flux Pen. It is very economical to use -- you don't need much, and I have had the same pen for months.
I rarely see any residue left when I use it. Kester also makes a "no-clean" 951 Flux Pen which might actually produce less residue.
Using flux really helps make a better solder joint -- even with a flux cored solder wire.
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I use a Kester 186 Flux Pen. It is very economical to use -- you don't need much, and I have had the same pen for months.
I rarely see any residue left when I use it. Kester also makes a "no-clean" 951 Flux Pen which might actually produce less residue.
Using flux really helps make a better solder joint -- even with a flux cored solder wire.
Thanks. Will try to order one of each today.