New 18W Superlite TMB/Arc Welder for a minute

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Re: New 18W Superlite TMB/Arc Welder!

Post by JMPGuitars »

TriodeLuvr wrote:
Fri 02/05/21 11:29 pm
Well, that was my point - rosin flux is much superior in terms of cleaning the joint. The sole reason "no-clean" was invented was to eliminate the need for factory assemblers to remove residual flux on the outside. Manufacturing employees in lower-volume applications, such as QA and repair, still often use rosin flux because it removes oxide more aggressively (i.e. cleans the joint) and flows solder better. Rosin flux also doesn't vaporize as rapidly as "no-clean," and that helps lesser-skilled workers produce good, shiny joints.

It's great that you're not having problems with "no-clean." Nevertheless, the differences between the two types and the purposes they're best suited to are facts well-understood by industry. There simply isn't a reason in this type of work to use anything other than rosin core solder.

Jack
Right, the separate flux is good for cleaning things that need it. In those cases, I use it to pre-clean / re-tin stuff outside and away from the build to avoid any mess. I usually use a rosin paste flux I can dip stuff into prior to dunking in my solder pot.

Some types of flux can be corrosive, and can potentially carry signals across them. Rosin core doesn't have that issue, but it still can hide the joint, making proper circuit inspection difficult or impossible. Of course rosin core isn't universally useful either.

If you or anybody else feels their soldering skills are inadequate to fully benefit from using no-clean solder (or any other type), I suggest watching and rewatching the soldering technique videos linked in my signature. Solder technique is always more important than most other things going into a build.
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Re: New 18W Superlite TMB/Arc Welder for a minute

Post by ViperDoc »

Problem noted:

When playing through this amp with single coils on any guitar, there is a very faint, fast ticking sound happening. When I switch to a humbucker, it completely disappears. It's not the guitar. Otherwise the amp sounds great. This ticking seems to accompany tremolo circuits, which I don't have. Bad cap or solder joint?
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Re: New 18W Superlite TMB/Arc Welder for a minute

Post by JMPGuitars »

Is your cellphone close by? Move it farther away if it is.
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Re: New 18W Superlite TMB/Arc Welder for a minute

Post by Bieworm »

ViperDoc wrote:
Sun 02/07/21 3:14 pm
Problem noted:

When playing through this amp with single coils on any guitar, there is a very faint, fast ticking sound happening. When I switch to a humbucker, it completely disappears. It's not the guitar. Otherwise the amp sounds great. This ticking seems to accompany tremolo circuits, which I don't have. Bad cap or solder joint?
I have that too sometimes. It is definitely the internet router. It's typical...
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Re: New 18W Superlite TMB/Arc Welder for a minute

Post by JMPGuitars »

Bieworm wrote:
Sun 02/07/21 5:06 pm
ViperDoc wrote:
Sun 02/07/21 3:14 pm
Problem noted:

When playing through this amp with single coils on any guitar, there is a very faint, fast ticking sound happening. When I switch to a humbucker, it completely disappears. It's not the guitar. Otherwise the amp sounds great. This ticking seems to accompany tremolo circuits, which I don't have. Bad cap or solder joint?
I have that too sometimes. It is definitely the internet router. It's typical...
Could be cellphone, wifi router, bluetooth, watch, etc...

Do you have copper shielding properly installed in your guitars?
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Re: New 18W Superlite TMB/Arc Welder for a minute

Post by ViperDoc »

Thanks for the tips.
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Re: New 18W Superlite TMB/Arc Welder for a minute

Post by Bieworm »

I shielded the guitars that need it. But there is one that keeps having that.. oh well... I'm fine with that..
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Re: New 18W Superlite TMB/Arc Welder for a minute

Post by ViperDoc »

Just a quick update:

When using 7189 tubes in an EL84 build, although the normal operating 7189 plate voltages are listed as higher handling, the recommended operating screen voltages are the same as EL84s. The B-node screen dropping resistors, therefore, will need to be increased to protect the screens when targeting higher 7189 plate voltages.

I designed my build for a slightly higher B+ of 364V rectified (running 120V into the PT 110V primary), so with the S-lite schematic values, that placed my 7189 screen voltages at 350 VDC, which is 20V over the maximum. My mistake for not checking that. I will up the screen resistor values, possibly replace my tubes and return and report!

As a quick test, I variac'd my AC down to 110V and the amp just sounds killer. KILLER. Not sure whether to marry my Brown Box to this amp or knock my power string down after the OT primary tap.
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Re: New 18W Superlite TMB/Arc Welder for a minute

Post by JMPGuitars »

ViperDoc wrote:
Mon 02/08/21 1:42 am
As a quick test, I variac'd my AC down to 110V and the amp just sounds killer. KILLER. Not sure whether to marry my Brown Box to this amp or knock my power string down after the OT primary tap.
Test your voltages at the 110VAC source, then adjust B+ to match at normal source voltage. You shouldn't need to replace the tubes, but if you do, send the old ones my way. ;) ;)
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Re: New 18W Superlite TMB

Post by ViperDoc »

I just installed a Metro Zero Loss effects loop after working out some voltages. After adjusting the levels, it sounds great. It did pull my power string voltages down a bit from its current draw, so I'll adjust it back up and I should be golden. To test the 7189s at their full plate voltage potential, I'll need to use a different transformer, but this amp sounds great as is.

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Re: New 18W Superlite TMB

Post by Bieworm »

ViperDoc wrote:
Sat 03/06/21 6:20 pm
I just installed a Metro Zero Loss effects loop after working out some voltages. After adjusting the levels, it sounds great. It did pull my power string voltages down a bit from its current draw, so I'll adjust it back up and I should be golden. To test the 7189s at their full plate voltage potential, I'll need to use a different transformer, but this amp sounds great as is.

Image
Looking sweet🙂
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