Videx Videoterm clone, no display output and no beep. Help? :)

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softwarejanitor wrote:What
softwarejanitor wrote:

What kind of soldering iron/station do you use?  I used to use a small Weller, but I upgraded a while back to a Yihua 939D+ which is a lot better.

 

Soldering takes a soft touch, using the right solder, the right temperature, etc.  Practice makes perfect.  If you are breaking things you are probably using too much pressure and maybe too much heat.

 

 

 It is a cheapy iron, but it does at least have temperature control. I figured out several things afterwards.

 

It takes a very long time to heat up, the tip was oxidised and I didn't tin it, and I was likely applying too much pressure. 

 

Basically I did everything wrong, but it was my first time holding a soldering iron! I am going to try a little more soon. It is something I would like to get at least competent at. 

 

Breaking the component was because I tried to remove it from the board when some legs weren't fully desoldered, and I snapped one of them. (Again this was just a throwaway item, not the Videx board)

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.
 
Akagi wrote:
 

making your own soft switch would probably be a good beginner soldering project. My version of one is here: https://github.com/btb/80ColumnCard/tree/main/hardware/SoftSwitch

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bradleyb wrote: Akagi wrote:
bradleyb wrote:
 
Akagi wrote:
 

making your own soft switch would probably be a good beginner soldering project. My version of one is here: https://github.com/btb/80ColumnCard/tree/main/hardware/SoftSwitch

 

 

I tried again today, tinned iron, 350*C, all I needed to do was solder two wires together...

 

Fresh copper strands of wire on both ends, held neatly in my helping hands.

 

I couldn't even tin the wire! The heat can't have been transferring from the iron at all. 

 

I am certain that while I might be bad at it, I'm not *this* bad...

 

So I returned the iron... Now I am iron-less. 

 

If I get another one, a better one, I will try something like that. Thanks! 

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Have a look at the Pinecil

Hey Akagi,

Have a look at the Pinecil soldering irons. Powered over USB C, but you'll want a grunty USB C power supply if you don't already have one. I have the TS100 soldering iron, which is the precursor and it's amazing!

They're that sweet spot of "relatively cheap" and "relatively excellent" which we all strive for.

PINECIL – Smart Mini Portable Soldering Iron - PINE STORE (pine64.com)

 

Chesh

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350 degrees C?  I don't think

350 degrees C?  I don't think that is right at all.   According to online conversions that's 662 degrees F which I think is way too hot. If solder isn't melting set to that you are probably right that the iron was faulty.   The spool of solder I just grabbed says on the label that the melting point is 368 degrees F.  Temp needed varies depending on the exact composition of the solder.  This spool is Sn63 Pb37.  The lead free crap seems to need hotter, but I don't buy that stuff anymore and trying to use up what I have left.  I usually run my Yihua soldering station just a bit over 400 degrees F, like 408-410.  It is switchable between C/F, but being from the US C temps mean little to me.

 

The Yihu 939D+ station I have is under $60 on Amazon.  It's nothing fancy but does work reasonably well.  There are a lot of nicer ones if you're willing to spend more $$$.

 

 

 

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softwarejanitor wrote:350
softwarejanitor wrote:

350 degrees C?  I don't think that is right at all.   According to online conversions that's 662 degrees F which I think is way too hot. If solder isn't melting set to that you are probably right that the iron was faulty.   The spool of solder I just grabbed says on the label that the melting point is 368 degrees F.  Temp needed varies depending on the exact c

 

I probed the iron with a thermocouple and it was reaching those temperatures. I was going from what I read online and saw in tutorial videos, 340 - 370C for lead free solder. 

 

Despite that, I had to touch the solder to the iron for maybe half a second before it would melt, I'm not sure if that is usual or not. But my main issue was that it didn't seem to transfer the heat into the component I was trying to solder, and the tip would oxidise pretty much immediately. 

 

So I would hold the iron underneath some bare copper wire for some time, and touch the solder to the wire, and it would not melt. 

 

I'm sure a lot of it is my inexperience, experienced solderers make it look extremely easy.

 

But surely it shouldn't be that difficult...  

I thought perhaps the solder was iffy, but I borrowed some from my Dad and it behaved the same so, I don't know! 

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I would recommend geting some

I would recommend geting some Sn63 Pb37 solder.  I got so frustrated with how poorly the "lead free" garbage works I won't buy it.  Good quality solder and a little solder flux makes it a lot easier.

 

An underpowered iron can also be frustrating sometimes if you are trying to solder on something that can suck up a lot of heat.  The soldering station I have makes things a lot easier than the old small irons I used to use.  It heats and re-heats much more quickly and makes it easier to maintain a steady temperature.

 

 

 

 

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CheshireNoir wrote:Hey Akagi
CheshireNoir wrote:

Hey Akagi,

Have a look at the Pinecil soldering irons. Powered over USB C, but you'll want a grunty USB C power supply if you don't already have one. I have the TS100 soldering iron, which is the precursor and it's amazing!

They're that sweet spot of "relatively cheap" and "relatively excellent" which we all for.

 

I like the look of that! As for a grunty USB power supply... I have my 80W phone power brick? I'm sure it will be okay. 

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softwarejanitor wrote:I would
softwarejanitor wrote:

I would recommend geting some Sn63 Pb37 solder.  I got so frustrated with how poorly the "lead free" garbage works I won't buy it.  Good quality solder and a little solder flux makes it a lot easier.

 

An underpowered iron can also be frustrating sometimes if you are trying to solder on something that can suck up a lot of heat.  The soldering station I have makes

Will try that too... PINECIL and lead solder on the shopping list for pay day. :) 

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A USB powered soldering iron

A USB powered soldering iron just seems like a bad idea to me.  Why not just get something that runs off wall power?

 

 

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Basic soldering technique
Akagi wrote:
I probed the iron with a thermocouple and it was reaching those temperatures.

You should be aware that measuring the temperature of a soldering iron tip is not trivial. If anything, pressing a thermocouple onto the tip would underestimate the true temperature because of the limited contact area. The way industry calibrates soldering temperatures is by using specially designed instruments like the Hakko FG-100. These work by means of a thermocouple made of three wires welded together in a 'Y' shape that the soldering iron is laid down upon. As the iron presses on the junction of the 'Y', it can flex because one of the wires is on a sprung pivot. This makes the area of contact relatively constant over different degrees of downward pressure. The true temperature still requires a tiny drop of molten solder between the iron and the 'Y' because without it the heat flow is too impeded for a proper measurement.

Incidentally, that model of calibrator is very frequently counterfeited on online markets, as are some of the lower end Hakko stations and their accessories.

 

650° F is a reasonable temperature for soldering with Sn60Pb40 solder. Users of lead-free alloys often use higher temperatures (unless the alloy used is a special low-melting type). Obviously the iron's temperature must be higher than the alloy melting point: imagine a cooler filled with water and ice in thermal equilibrium. Its temperature is clearly 0° C, which is the melting point of ice. Yet if you drop an ice cube into the cooler, it won't melt.

Sometimes when you are working with small components, you want heat transfer to be slower, so 600° F may be considered safer. Much below that, and even Sn63Pb37 (MP = 361° F) won't melt. The thermal conductivity of a solder wire spool means that even it by itself won't be melted by a 400° F iron, unless the wire is cut into a short section. Using too low a soldering temperature can be a factor in cold joints, a soldering defect that makes the workpiece unreliable.

Soldering training on the basic level is about keeping the tip tinned with clean solder. If the iron is ever hot without clean solder protecting it, it will begin to oxidize. Oxidized metal cannot wet solder at all, so it stops being usable unless it is reactivated. The consequence is that the most frequent actions during soldering have nothing to do with the workpiece at all. It is the necessary steps of maintaining the iron's performance by cleaning it and re-tinning it. If this is not followed religiously, it will stop working in seconds and become junk.

Since the advent of brass wire "sponges" like the Hakko 599B, they have rapidly displaced the traditional wet sponges, although those are still used by some operators. Either one can be used to clean the tip, but the brass dry type tends to be more effective without the need to learn as much technique. It also means you don't need to keep the sponge wet with its accompanying requirement for distilled water at the bench etc. and it reduces messy spatter.

The tip must always be tinned immediately after cleaning and must be put away freshly tinned.

The above is all about simply getting solder to melt onto the iron tip: to be able to effectively solder or desolder components on a workpiece, you must also understand the application of flux which is a different topic.

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Tinning

For tinning wire, it helps to know that solder moves towards the source of heat. One way to do it is to dip the wire ends in liquid flux, then get a large bead of molten solder on a large chisel or bevel tip. Then you can simply wipe the wire across the tip and the flux will help it flow all over the wire end. With both wire ends being tinned it will be possible to solder them together (although this is a fiddly operation and "helping hands" clamps or similar would be required to prevent a cold joint).

The problem with wires soldered together is two-fold. First, if the wires are stranded, solder will to some extent wick up between the strands. This contributes to the insulation melting which is obviously bad. It also stops the stranded wire from being flexible at some point up inside the insulation, so there is an increased risk of breaking. Second is that while solder has high tensile strength, its shear strength is not as good, so the soldered wires may break apart under stress or vibration. When soldering was used to join telegraph wires, a special knot called the Western Union Splice was used to strengthen the joint.

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Thanks both, that is very

Thanks both, that is very interesting / helpful.

 

It does seem to me that an experienced solderer probably wouldn't have had much issue with the cheap iron then, past perhaps just finding it mildly annoying at times. 

 

And I underestimated how much cleaning and tinning was required. 

I also did not use DI water on the sponge, just regular filtered tap water.

 

And I did not use flux, because I understood that it was not needed when using flux core solder.

 

The solder was 0.6mm rosin core 99.3% tin and 0.7% copper with a supposed melting point of 227*C or 440*F.

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synergy

There may be a baneful synergy between the chemistry of LF solder, elevated temperature, and minerals in tap water. I'm not sure if it has been specifically studied. Tap water also contains halides so there may be a lot happening there.

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I'm not sure I agree with 600

I'm not sure I agree with 600+ degree F temps being necessary for Sn 63 Pb 37 solder.  The Yihua 939D+ soldering station doesn't even go up that high.  480 degrees F is as high as it goes.  And as I mentioned before, I usually run the iron at 408-410 degrees F (which shows around 766 degrees C if I push the C/F button) and have no trouble at all making proper solder joints.  The kind of statiion I use is fairly popular, so I can't imagine I'm the only one around who uses one like it.

 

Lead free solder seems to require a setting around 440 degrees F to melt reliably.  I just find that it does not work as well as leaded solder.

 

 

 

 

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softwarejanitor wrote:I'm not
softwarejanitor wrote:

I'm not sure I agree with 600+ degree F temps being necessary for Sn 63 Pb 37 solder.  The Yihua 939D+ soldering station doesn't even go up that high.  480 degrees F is as high as it goes.  And as I mentioned before, I usually run the iron at 408-410 degrees F (which shows around 766 degrees C if I push the C/F button) and have no trouble at all making proper solde

Now that I'm looking at it, I wonder if I have been reading the button setting wrong on this thing...  Hmmm...

 

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softwarejanitor wrote
softwarejanitor wrote:
softwarejanitor wrote:

I'm not sure I agree with 600+ degree F temps being necessary for Sn 63 Pb 37 solder.  The Yihua 939D+ soldering station doesn't even go up that high.  480 degrees F is as high as it goes.  And as I mentioned before, I usually run the iron at 408-410 degrees F (which shows around 766 degrees C if I push the C/F button)&

 

 

Yes you have C and F flipped it seems. (or the machine does!)

 

But knowing the temperature you solder at is helpful nonetheless haha. 

 

766*F is 408*C

 

408*F is about 209*C 

 

I apologise for the different units of measurement causing confusion :D 

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softwarejanitor wrote:A USB
softwarejanitor wrote:

A USB powered soldering iron just seems like a bad idea to me.  Why not just get something that runs off wall power?

 

 

USB C can deliver a lot of watts these days, is a standard, and can also mean, in a pinch, you can power your soldering iron off a power brick.

What's not to love? A heck of a lot of people out there are using these. They're an excellent choice for a versatile "first soldering iron". Heck. I want one as my fourth soldering iron.

They take standard tips, which are cheaply available, so you can have a couple of different tips on hand for different jobs :-)

 

Basically it's the next step up from my TL100 and that's the best soldering iron I've ever used, and while I haven't used Wellers or the like, it far outperforms my pervious $150AUD soldering iron for a fraction of the cost.

 

Join uss! It's bliiiisss!

 

Chesh

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If I might address the

If I might address the original topic briefly, 80 columns is now working after replacing the 4013! :D

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CheshireNoir wrote
CheshireNoir wrote:
softwarejanitor wrote:

A USB powered soldering iron just seems like a bad idea to me.  Why not just get something that runs off wall power?

 

 

USB C can deliver a lot of watts these days, is a standard, and can also mean, in a pinch, you can power your soldering iron off a power brick.

What's not to love? A heck of

 

Might I ask what your other irons are, and in what ways you find the PINECIL better? 

 

I can get the iron another member recommended for around the same price it seems. And that comes with all the bits and pieces. 

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My other iron leading up to

My other iron leading up to the TS100 (Which the Pinecil is a replacement for) was a generic workstation soldering iron from Altronics. It had no temperature display (only an LED) and it took ages to heat up.

The TS100 is very quick to heat up (Under 1 minute to get to 340c), responsive, has a temperature display built right into the work handle, and has override buttons right in the work handle too. It's light, self contained (I use it with an old laptop power supply as the TS100 doesn't support USB C. It was one of the improvements in the Pinecil)

I've got 3 different tips for mine and it's quick to swap which is great for switching from SMD to thru hole.

Here's Hack-a-Day reviewing it: Review: Pine64 Pinecil Soldering Iron | Hackaday

 

Chesh

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I dunno...I have a real hard

I dunno...

I have a real hard time trusting that the Pinecil is a decent soldering iron.

Maybe for the odd job here and there you can get away with it in a pinch, but for actual "work" which often involves hours of use at a time, nothing beats the durability (not to mention constant duty cycle) of a decent temperature controlled soldering station.

Good ones from Weller can be had for $100 or so and they can basically run non-stop.

 

Soldering is a time-temperature affair.  If your tip temperature is low then you need to apply heat for a longer time to get a good joint.  I prefer a hotter iron and a lighter touch.  (careful with old electronics - 650 is sometimes hot enough to de-laminate solder pads from old phenoloic boards)  

Generally I use 630°F-650°F for soldering and no more than 675°F for de-soldering.  Often I'll use paste flux dispensed from a syringe and add some low-melt solder to the existing joint before I attempt to desolder it (with either a suction tool or solder wick).

 

 

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