Date   
Re: 50W Amp - Photo of T2 Installed

 

Good lord... I wish there was a way to edit. My reply above should read:
The only photo of the assembled board shows a side view and no details of how the leads are routed. What I would call the top leads is pretty straight forward as long as you get the correct lead in the correct hole. The way the toroid is wound the bottom leads cross from nearly the same point as the top leads to the opposite side of the toroid. If that's how it is then I'll continue on. It doesn't look right from a board design perspective and that makes me question what I've done.

--
73
NE5U

Mike

Re: 50W Amp - Photo of T2 Installed

 

The only photo of the assembled board shows a side view and not details of how the leads are routed. What I would call the top leads is pretty straight forward as long as you get the right lead in the same hole. The way the toroid the bottom leads cross from nearly the same point as the top leads to the opposite side of the toroid. If that's how it is then I'll continue on. It doesn't look right from a board design perspective and that makes me question what I've done.

I would ask anyone to disassemble their amp just for this. 
--
73
NE5U

Mike

Re: 50W Amp - Photo of T2 Installed

ajparent1/KB1GMX
 

The 7 pictures in the manual are not adquate?   They are fairly high resolution.

If not what view would be useful?  Mine is assembled right now so taking
a shot would require disassembly.

Allison
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50W Amp - Photo of T2 Installed

 

Does anyone have a good photo of how T2 looks when it's installed on the board. I have the leads ohmed out and marked I'm just struggling with how the underside leads traverse under the toroid from the opposite side. If that's how it's supposed why not just put traces and hols on the other side? I haven't trimmed or soldered anything yet...
--
73
NE5U

Mike

Re: 50 Watt Amp Final Transistors

ajparent1/KB1GMX
 

No, none as adding lead length via sockets is a bad thing.

With popper care board damage should  not happen.

Hint if you destroy them,  disassemble, cut the leads at
the package,  (they are dead!) and extract the leads one
at a time with a sufficiently hot iron and tweezer.

Clear the holes by heating the solder and using inertia
(sudden stop while molten) should clear the hole.

Do not drill or use pins or try to poke the tip of the iron in.
That often does more damage.

Allison
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Re: 50 Watt Amp Final Transistors

George Korper
 

Allison and Others,
Anyone have any tips on a way to install the finals on a temporary basis to avoid
ruining the board? That way if i have some other mistake which blows the finals
I could save a lot of grief and perhaps the rest of my work!
George

On Sat, Feb 29, 2020 at 5:04 PM George Korper via Groups.Io <georgekorper=gmail.com@groups.io> wrote:
BTW just ordered from Digikey.

On Sat, Feb 29, 2020, 2:48 PM ajparent1/KB1GMX <kb1gmx@...> wrote:
IRF510 from any source not Ebay or other random sources.

Typically  I use Digikey and Mouser, Allied,  and Jameco with zero issues.
Another is RFparts.com,  the real McCoy at real prices.

The problem with any RF device and a long list of them common to ham
and hobby use is buy cheap, get cheap counterfeits.  I buy them from known
sources usually at higher (fair) prices I get what I wanted and quality or at
least a firm I can actually go back to.

The beauty of IRF510 is typical price is well under 1.25$ each from reputable sources.
and at last buy a few weeks ago I got 10 for 88 cents each (VIshay IRF510).


Allison
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Re: 50 Watt Amp Final Transistors

George Korper
 

BTW just ordered from Digikey.


On Sat, Feb 29, 2020, 2:48 PM ajparent1/KB1GMX <kb1gmx@...> wrote:
IRF510 from any source not Ebay or other random sources.

Typically  I use Digikey and Mouser, Allied,  and Jameco with zero issues.
Another is RFparts.com,  the real McCoy at real prices.

The problem with any RF device and a long list of them common to ham
and hobby use is buy cheap, get cheap counterfeits.  I buy them from known
sources usually at higher (fair) prices I get what I wanted and quality or at
least a firm I can actually go back to.

The beauty of IRF510 is typical price is well under 1.25$ each from reputable sources.
and at last buy a few weeks ago I got 10 for 88 cents each (VIshay IRF510).


Allison
-------------------------------
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Re: 50 Watt Amp Final Transistors

George Korper
 

Hi Allison,
I had a good amp that needed new
Finals. 20 meters.

 I ordered on Amazon. Put in replacements. No data, looked kind of cheap, etc.

Checked bias using current limiting supply. All ok. Pot is barely above anti clockwise 

Left practice mode. Output at 12 volts 10 watts as I raised voltage it seemed low output. At 20 volts it was working but I started to hear a ripple develop.  20 watts output for 10 seconds. This was half the output of the supplied transistors.

Then they blew and supply tripped out. 

Is this behavior consistent with poor quality mosfets?

On Sat, Feb 29, 2020, 2:48 PM ajparent1/KB1GMX <kb1gmx@...> wrote:
IRF510 from any source not Ebay or other random sources.

Typically  I use Digikey and Mouser, Allied,  and Jameco with zero issues.
Another is RFparts.com,  the real McCoy at real prices.

The problem with any RF device and a long list of them common to ham
and hobby use is buy cheap, get cheap counterfeits.  I buy them from known
sources usually at higher (fair) prices I get what I wanted and quality or at
least a firm I can actually go back to.

The beauty of IRF510 is typical price is well under 1.25$ each from reputable sources.
and at last buy a few weeks ago I got 10 for 88 cents each (VIshay IRF510).


Allison
-------------------------------
Please reply on list so we can share.
No direct email, it goes to bit bucket due address harvesting in groups.IO

clock and gps #clock

Don Blachura
 

Only getting half the screen on my clock. See heart and date, but
nothing else.? What failed?

Don...w2xb

Re: 50 Watt Amp Final Transistors

ajparent1/KB1GMX
 

IRF510 from any source not Ebay or other random sources.

Typically  I use Digikey and Mouser, Allied,  and Jameco with zero issues.
Another is RFparts.com,  the real McCoy at real prices.

The problem with any RF device and a long list of them common to ham
and hobby use is buy cheap, get cheap counterfeits.  I buy them from known
sources usually at higher (fair) prices I get what I wanted and quality or at
least a firm I can actually go back to.

The beauty of IRF510 is typical price is well under 1.25$ each from reputable sources.
and at last buy a few weeks ago I got 10 for 88 cents each (VIshay IRF510).


Allison
-------------------------------
Please reply on list so we can share.
No direct email, it goes to bit bucket due address harvesting in groups.IO

Re: 50 Watt Amp Final Transistors

Adam
 

Hi George,
What Hans said.
I bought a bunch and they work great.
https://au.rs-online.com/web/p/mosfets/9190023/

Re: 50 Watt Amp Final Transistors

Hans Summers
 

Hi Paul

Most of the parts for the QRP Labs kits, I buy the correct amount for the number of kits, based on the number of PCBs made. If I buy a lot extra to be able to offer spares, it would increase the costs, logistics problems and the admin headaches... producing kits is already hard enough without multiplying it all by offering all the components too... all the components used in QRP Labs kits are generally easy to find, here aren't any difficult to find components... the theory goes that if people need spares they should be quite easy to find.

73 Hans G0UPL 

On Sat, Feb 29, 2020, 21:55 K2DB Paul Mackanos <paul.mackanos@...> wrote:
Hans, why don't you just add it under components in your shops ?

On Sat, Feb 29, 2020, 1:26 PM Hans Summers <hans.summers@...> wrote:
Hi George 

I tested 6 different supplier IRF510 before choosing the one used in the QRP Labs kits. It's not one you will be able to buy in single quantities without going through all that extensive testing again. I think you should just get the Digikey IRF510 made by Vishay, Digikey part number IRF510PBF-ND, I'm sure it will be fine. 

73 Hans G0UPL 

On Sat, Feb 29, 2020, 20:28 George Korper <georgekorper@...> wrote:
Hi,
I need a trusted source and part number with link for the best replacement 
IRF 510 finals. 
Thanks,
George

Re: 50 Watt Amp Final Transistors

K2DB Paul Mackanos
 

Hans, why don't you just add it under components in your shops ?


On Sat, Feb 29, 2020, 1:26 PM Hans Summers <hans.summers@...> wrote:
Hi George 

I tested 6 different supplier IRF510 before choosing the one used in the QRP Labs kits. It's not one you will be able to buy in single quantities without going through all that extensive testing again. I think you should just get the Digikey IRF510 made by Vishay, Digikey part number IRF510PBF-ND, I'm sure it will be fine. 

73 Hans G0UPL 

On Sat, Feb 29, 2020, 20:28 George Korper <georgekorper@...> wrote:
Hi,
I need a trusted source and part number with link for the best replacement 
IRF 510 finals. 
Thanks,
George

Re: 50 Watt Amp Final Transistors

George Korper
 

Thank you;

will do!


On Sat, Feb 29, 2020, 12:26 PM Hans Summers <hans.summers@...> wrote:
Hi George 

I tested 6 different supplier IRF510 before choosing the one used in the QRP Labs kits. It's not one you will be able to buy in single quantities without going through all that extensive testing again. I think you should just get the Digikey IRF510 made by Vishay, Digikey part number IRF510PBF-ND, I'm sure it will be fine. 

73 Hans G0UPL 

On Sat, Feb 29, 2020, 20:28 George Korper <georgekorper@...> wrote:
Hi,
I need a trusted source and part number with link for the best replacement 
IRF 510 finals. 
Thanks,
George

Re: 50 Watt Amp Final Transistors

Hans Summers
 

Hi George 

I tested 6 different supplier IRF510 before choosing the one used in the QRP Labs kits. It's not one you will be able to buy in single quantities without going through all that extensive testing again. I think you should just get the Digikey IRF510 made by Vishay, Digikey part number IRF510PBF-ND, I'm sure it will be fine. 

73 Hans G0UPL 

On Sat, Feb 29, 2020, 20:28 George Korper <georgekorper@...> wrote:
Hi,
I need a trusted source and part number with link for the best replacement 
IRF 510 finals. 
Thanks,
George

50 Watt Amp Final Transistors

George Korper
 

Hi,
I need a trusted source and part number with link for the best replacement 
IRF 510 finals. 
Thanks,
George

Re: LED question

George Korper
 

Thanks Alan. Just the answer I needed.


On Sat, Feb 29, 2020 at 10:06 AM Alan G4ZFQ <alan4alan@...> wrote:
George

> What is the spec for 3 mm LED that is on the board?

It must be an ordinary high brightness LED. 470 ohms in series from 5V
is not going to damage any other LED. Ones that are not so high
brightness will just be dimmer.

Bending the leads must be done carefully, hold the wire close to the LED
with fine-nose pliers. Do not overheat when soldering.

73 Alan G4ZFQ

> There seems to be  differences in quality for this 'Generic" part,
> I was careful in bending the original, Not sure bending the lead as
> pictured
> is the best method. I think I should have  bent it around a knife blade.
> I could have also left  it a teeny tiny bit above the board, to keep
> from stressing it in alignment with the case
> and used a tweezer in the process.



Re: LED question

Alan G4ZFQ
 

George

What is the spec for 3 mm LED that is on the board?
It must be an ordinary high brightness LED. 470 ohms in series from 5V is not going to damage any other LED. Ones that are not so high brightness will just be dimmer.

Bending the leads must be done carefully, hold the wire close to the LED with fine-nose pliers. Do not overheat when soldering.

73 Alan G4ZFQ

There seems to be  differences in quality for this 'Generic" part,
I was careful in bending the original, Not sure bending the lead as pictured
is the best method. I think I should have  bent it around a knife blade.
I could have also left  it a teeny tiny bit above the board, to keep from stressing it in alignment with the case
and used a tweezer in the process.

Re: clock and gps #clock

Carl NQ3U
 

Don,
when I built mine, being a typical guy, I didn't read the manual very closely.  When I powered it on and got past the diagnostic screen the clock started and I was getting indications that the GPS was receiving signals, but no LAT/LON displayed!!!  I spent some time looking at all the boards, components, soldering, and everything looked correct to my eyes.  It was a little confounding until I RTFM, Page #8 GPS mode Settings are initially 0 - GPS is not used at all. The kit is in free-running mode, it will run from it's 20MHz crystal oscillator.  I changed that setting to 2 and PRESTO, I magically got LAT/LON displayed.
There are also some programming hints and examples of how others have programmed their displays on the QRP Lab Web site.
I immediately upgraded my display from the 2 line display to the 4 line display and love it.
I'm still working on a custom case layout for it.  The case is the difficult part for me.

73,
Carl
NQ3U 

Re: clock and gps #clock

David Griffiths
 

And you need to set the GPS flag in the menu.