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Re: Soldering gun or iron
I have learnt to live with just about any iron. What matters really is a nice clean tip. These days they are tips that don't pit. I like those. Keep a good sponge, wipe them often. - f
By Ashhar Farhan · #44695 ·
Re: Soldering gun or iron
The images of what I needed minimum. It looks like the station is not available but there are ones with more features around 70$. Chris
By Christopher Miller · #44694 ·
Re: Soldering gun or iron
I find that holding my own hands sill enough to put a part the size of a couple grains of rice on a pcb without lifting a pad or tossing it on the floor is difficult for me even. Im 33! It looks to me
By Christopher Miller · #44693 ·
Re: UBitX Transmit Problem Fixed
All I know is I wasn’t getting the correct voltages on Q90. It was 0 volts dc on all three pins. I was also losing the transmit dc in the vicinity of R84. So I replaced them both. Yeah, I know, kind
By Guy N7BIR <sgbridge@...> · #44692 ·
Blew the irf510's up, substituted irfp260's in there place... #ubitx-help
Well, pushing the limits on the irf510 mosfets, they caved on me. So, digging through my junk I found four irfp260's and soldered them in as an effort to get back on the air. So far, it seems to work,
By Ghericoan · #44691 ·
Re: Soldering gun or iron
Likewise somewhere I have my original Weller Soldering Gun from around 1958! Yes, it still works but I don't really have a use for it. I do have a huge Weller soldering iron for replacing Can
By Dave Bottom <ars.kd6az@...> · #44690 ·
Re: Micro BitX No Audio TDA2822?
Some of these clones seem to blow for no particular reason. I think we primarily must limit the supply voltage, not so much the current under load. Though they are really good at dealing with
By Jerry Gaffke · #44689 ·
Re: Micro BitX No Audio TDA2822?
The DPAK package is perfect. http://uk.farnell.com/stmicroelectronics/l78m05abdt-tr/ic-v-reg-5-0v-smd-dpak-3-7805/dp/1366575
By Joe Puma <kd2nfc@...> · #44688 ·
Re: Micro BitX No Audio TDA2822?
Quiescent current into the TDA2822 is around 6ma, peaks can be 1 Amp. Though?100ma might be sufficient for moderate speaker volumes. You would need two resistors for a voltage divider, and maybe
By Jerry Gaffke · #44687 ·
Re: Micro BitX No Audio TDA2822?
One could use a voltage drop resistor. The higher the current draw, lower would be the voltage to the TDA2822 [email protected]> wrote:
By Ashhar Farhan · #44686 ·
Re: Micro BitX No Audio TDA2822?
Regarding Joe's suggestion of using the Raduino's LM7805 to power the TDA2822: One objection I would have is the extra wire, needs to be dealt with every time? I unplug the Raduino.? Though not a
By Jerry Gaffke · #44685 ·
Re: 13.8 v power supplies safe for bitx?
Jerry, I'm not sure everyone understands what foldback current limiting is. Your message 40729 explains it well. In action it is like a fuse. The power supply opens the power lead until the operator
By Tim Gorman · #44684 ·
Re: RD transistors, unobtanium?
IRF510 and IRF512 both have a Vds max of 100v. According to these guys, at least, not many IRF512 datasheets out there: ? ??http://www.njsemi.com/datasheets/IRF510%20-%20IRF513.pdf The IRF510 has a
By Jerry Gaffke · #44683 ·
Re: Soldering gun or iron
It might be worth looking for some auctions as well. I've never understood how I did anything with solder before my metcal sp-200 iron I've had for 20 yrs now. It's way more iron than I need and
By N1AFF - formerly KB1JPW · #44682 ·
Re: 13.8 v power supplies safe for bitx?
True.? The standard current limiting supply I described is not something to lean on to avoid driving the final too hard, that's not what I was suggesting. If there's a current limit on the finals,
By Jerry Gaffke · #44681 ·
Re: Micro BitX No Audio TDA2822?
Could work, first time this was suggested. An extra wire, the Raduino regulator would get hotter. ?
By Jerry Gaffke · #44680 ·
Re: RD transistors, unobtanium?
Title. Fake news. Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois Owner – Operator Villa Grand Piton -
By K9HZ · #44679 ·
Re: RD transistors, unobtanium?
Where did this info come from? RF Parts shows these in stock. I just purchased both the RD16HHF1 and RD15HVF1 in quantity from RF parts and received them in 2 days. Mitsubishi still shows these on
By Dave Bottom <ars.kd6az@...> · #44678 ·
Re: RD transistors, unobtanium?
Actually, the closest available MOSET to the IRF510 is the IRF512, which is the same device, only it is rated for a drain voltage of 100v. It goes by other numbers as well. There are many devices
By John Backo · #44677 ·
Re: 13.8 v power supplies safe for bitx?
When you current limit the PA you are doing the same thing that happens when you overdrive a linear amp and cause flat-topping, i.e. the PA is driven out of its linear range. That causes spurious
By Tim Gorman · #44676 ·