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Al, the rig behind is a forty-9er. It has the W8TEE/K2ZIA vfo, a lm386 audio amp, a hi-per-mite cw filter, a k1el contest keyer and just for fun, a second arduino board for blue tooth control of the functions via android device. I'm using a kindle fire for the remote. You can check my QRZ page and see the hood up with labels. The tuning via android is pretty primitive. I'm using a 12v motor driving a second encoder that is switched in and out and turned on with relays. It was just a project to keep my hands and mind busy while I was laid up with sickness. Surprisingly it turned out pretty good. I would love to be able to "really" control the volume and functions of the encoder with push buttons. I have a W8TEE B40 unit built up with a 3.5 inch display, and would love to build a second bitx with no knobs and only push buttons to give it a high tech look. I can do this by "cheating", but I'm sure someone out there can do it for real. I am much better with a hacksaw and a file than I am with any kind of electronics, and if I do have circuit trouble, I will need to rely on the amazing people on these forums to bail me out unless it is pretty basic stuff.
A little youtube with a short demo
The 40 meter amp beside the rig is 2 irf510s on a pre-built board out of Indonesia. I just added a step up converter to run it on 27volts, heatsinked, added a qrp labs LPF and cased it. On a probably very inaccurate meter, I'm seeing 19 watts out with 3/4 in.
Progress this evening was finishing the power board with outputs of ?12v raw, 5v, 9v, and 12v regulated. This should give me some power options on any mods I may want to do.?
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The BitX40 with no mods is ready to be powered...except for the microphone. Today I worked on the PTT bar. A parallel pair of switches should take care of me pushing on one end of the bar or the other without any ill effects. I think I had rather work on metal than pvc. I'll try to get the mic operational, do a wiring check, then power on in the next few days.  
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My BITX-40 is built in a wooden and clear acrylic case so all of my build, can be seen in or out.? Keeping in line with this type of construction, I decided to make a hand mic out of wood also, which is nearly complete as I write this.? Then with a desk mic in mind, with push to talk, and a hold button to follow?built out of?wood, I was thinking about a design.? At a ham swap meet last week, I found just what I am going to use for my wood design.? So for $2.00, I now have a pattern and probably a mic that works.? It is a rather small, Radio Shack, Realistic, dynamic, catalog no. 21-1176?that is?less than 8 inches tall.? It is?all plastic except a metal base for weight.? It comes apart easily with screws, so there is no breaking plastic tabs off or anything to change the mic element to the electret that came with the BITX kit.? Attached is a photo of the mic.? 73, Karl, KO8S
On Thursday, August 17, 2017 9:37 PM, RCC WB5YYM <curtis03@...> wrote:
The BitX40 with no mods is ready to be powered...except for the microphone. Today I worked on the PTT bar. A parallel pair of switches should take care of me pushing on one end of the bar or the other without any ill effects. I think I had rather work on metal than pvc. I'll try to get the mic operational, do a wiring check, then power on in the next few days.  
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That will convert quite nicely, and even meet Dexter's approval. I think it was him who wanted the locking button for rag chews. I plan on keeping a heavy book nearby to lay on my key when long transmissions are needed. A real bargain too.
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I'm using what used to be an old icom desk mic. The element was replaced with the one that comes with the BitX. The button moves really easy into the lock position, too easy! 99% of the time I press the PTT, it locks.
Vince.
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On 08/18/2017 07:07 PM, RCC WB5YYM wrote: That will convert quite nicely, and even meet Dexter's approval. I think
it was him who wanted the locking button for rag chews. I plan on
keeping a heavy book nearby to lay on my key when long transmissions are
needed. A real bargain too.
--
Michigan VHF Corp.
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A piece of ballpoint-pen spring ought to cure that - form it to a 'hairpin'? I'm an inveterate user of 'what's lying around' - -or in the rubbish. :)
73, Dex
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I lit the little radio today, and no smoke. Made no tests on on the current, just turned it on and listened. The radio sounds really nice. I do have tuning clicks with no antenna disconnected, but with the antenna connected, I don't hear them at all. I checked the power out and thought it was down. I do not have a pep meter, but the meter would only kick up to about 1 watt on transmit. At that power, it looks to be driving the pair if irf510's to about 20 watts, maybe a little more if I had a pep meter. If it sounds decent on transmit I will be tickled pink. ?I guess I need to try and make a contact. I've got butterflies.... I kind of like the tuning. It took me a minute to catch on, but I'm slow that way. It is pretty cool 
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I agree, this little radio sure is fun, especially with respect to the price!? 73, de KO8S, Karl
On Sunday, August 20, 2017 5:38 PM, RCC WB5YYM <curtis03@...> wrote:
I lit the little radio today, and no smoke. Made no tests on on the current, just turned it on and listened. The radio sounds really nice. I do have tuning clicks with no antenna disconnected, but with the antenna connected, I don't hear them at all. I checked the power out and thought it was down. I do not have a pep meter, but the meter would only kick up to about 1 watt on transmit. At that power, it looks to be driving the pair if irf510's to about 20 watts, maybe a little more if I had a pep meter. If it sounds decent on transmit I will be tickled pink. ?I guess I need to try and make a contact. I've got butterflies.... I kind of like the tuning. It took me a minute to catch on, but I'm slow that way. It is pretty cool 
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Added a couple 5v relays for keying and external control. Waiting for a couple of chassis mount phono jacks. I know I had some ....somewhere without ordering. The board will plug into any slot and operate the same. I need to pull the bitx board and add the protection diodes, but I'm having too much fun just listening to this nice little receiver and the DX it manages to find. Band has been open to Australia from here, but no contacts with low power. Stripes on the board are with sharpie ala' Farhan's numbering system. Just helps these eyes get things lined up. 
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I decided to work on the rig a little rather than "stalk" the band tonight. Loaded Allard's 1.20.1 software. Wired out the function switch. Having A and B vfos is nice. It seems USB does not have as much band noise as LSB???? Hoping to get the CW mode working on the rig before long. I have yet to touch anything on the main board. It seems a shame for me to place my unsteady hands, gripping a heated instrument of potential destruction, on such a nice product that has been working so well, but in the spirit of adventure, and probably stupidity, this project must go forward. Added a little ?board to get all the grounds tied down. Added pins for the connection to D4, D5, D6 and D7 and a calibrate switch.? 
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BTW .. with Allards Sketch you don't need a Calibrate switch any more as calibrate is included in the settings menu. So long as you?
have a function button you can do calibration. ?You mentioned the USB sensitivity is low. ?Did you remove C91 and C92 off of the RF board?
With these removed the USB sensitivity is much improved and there is no impact on LSB. These are redundant parts that are there for the analog VFO
implementation which has been replaced by the Raduino so there is no impact other than to improve USB operation.?
Cheers?
Michael VE3WMB / VA2NB?
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No, I did not remove C91 and C92. Thanks for the heads up on this Michael.
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Finished the mods to the board for Allard's software. I am amazed at what he made this little rig do. I now have a CW contact under my belt, and hope to make many more. I was not pleased with how the audio sounded after the side tone modification, so I undid it and used the side tone from the keyer. This also eliminated the spot function. I will take another look at this as I have time. I also ran into a problem, that I think was RF from the amplifier getting into the keyer. I did a reset and rerouted some cables and the problem went away. I'm hoping a handful of bypass capacitors, strategically placed, and the cover put on will cure the weird stuff.?
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Yes the sidetone does leave a bit to be desired. No doubt you experienced a surging in the tone volume, where it starts out low and increases to a level
that is fairly loud. ?A few of us have surmised that this is due to a rather large electrolytic cap on the output of the LM386 that is charging.?
I tried moving the sidetone injection to before the audio amp but found that after about a second I was losing sidetone. A closer inspection of the?
schematic of the BITX40 revealed that the supply voltage to the LM386 is getting removed during TX, so that explains the loss of sidetone.
Instead I built a small sidetone R/C filter according to the instructions in the manual for the K1EL keyer kits (manual online) and replaced one of the?
resistors with a trimmer pot so I could fine tune the level of the sidetone and this helps a lot. ?One thing I did notice is that this "sidetone level surging"
seems to be much less noticeable with my Koss CS-100 headset (32 ohm impedance headphone) than with an 8 ohm speaker. ?
One other mod that I highly recommend to improve the CW experience is anti-thump. I used the one documented in message 25871.
I still get some popping on the RX-> TX transition but it is reduced to the point where it is not uncomfortable to use headphones.?
I did some experimentation with the value of the resistor that is used to discharge the cap on PTT release with little success. I believe the?
the remaining noise I am hearing is a result of the reconnection of the supply voltage to the LM386 on the switch to RX.?
Cheers?
Michael VE3WMB / VA2NB?
P.S. I had a friend record my Bitx40 CW signal over the air and send me a snippet and I must admit that it sounds pretty good. No clicks, chirps or?
other artifacts. The keying sounds a little bit hard but it is not objectionable. IMHO it sounds a bit like an IC-703+.?
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Bent the cover today and checked it for fit. I couldn't resist sliding the "junk" over to one side of the bench to see how the home brew station would fit together. I also had an issue with the output jumping up and down, and upon taking a further look, I found the wiper on RV136 only held by the "crimp" on one side. When I touched it, it all came apart. I carefully bent up the side that was originally unattached, placed the wiper back on, and pushed the "crimp" back down. All is good again, and I have it detuned to 1 watt out, to drive the pair of irf510's. Not finished, but getting closer. ?The leaning display is driving me nuts. Got to do some fixing on that. Thinking about duct taping my head over to one side, or possible putting one side of my chair on a couple of books.?  
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Looks good!
Vince.
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On 09/04/2017 10:00 PM, RCC WB5YYM wrote: Bent the cover today and checked it for fit. I couldn't resist sliding
the "junk" over to one side of the bench to see how the home brew
station would fit together. I also had an issue with the output jumping
up and down, and upon taking a further look, I found the wiper on RV136
only held by the "crimp" on one side. When I touched it, it all came
apart. I carefully bent up the side that was originally unattached,
placed the wiper back on, and pushed the "crimp" back down. All is good
again, and I have it detuned to 1 watt out, to drive the pair of
irf510's. Not finished, but getting closer. The leaning display is
driving me nuts. Got to do some fixing on that. Thinking about duct
taping my head over to one side, or possible putting one side of my
chair on a couple of books.
--
Michigan VHF Corp.
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This is very clearly in the category of "knock it off, you're making the rest of us look bad!" Well, me anyway. ;-)
Those are beautiful. :-)
-Mark
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On Sep 4, 2017, at 7:00 PM, RCC WB5YYM < curtis03@...> wrote: Bent the cover today and checked it for fit. I couldn't resist sliding the "junk" over to one side of the bench to see how the home brew station would fit together. I also had an issue with the output jumping up and down, and upon taking a further look, I found the wiper on RV136 only held by the "crimp" on one side. When I touched it, it all came apart. I carefully bent up the side that was originally unattached, placed the wiper back on, and pushed the "crimp" back down. All is good again, and I have it detuned to 1 watt out, to drive the pair of irf510's. Not finished, but getting closer. ?The leaning display is driving me nuts. Got to do some fixing on that. Thinking about duct taping my head over to one side, or possible putting one side of my chair on a couple of books.?
<20.jpg><19.jpg>
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Those are mighty kind words Mark. I have borrowed ideas, it seems, from just about everyone on this board, and was fortunate to have stashed some aluminum away, back in the 1980's that was just . I suppose a person might say, I've been working on this rig (at least the case) since the late 1980's. hahaha I hope my build gives some ideas to some other builder. I just wish I was decent at the technical side of this stuff.?
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Hi Randall, Your homebrew station looks great! Where are you getting your large knobs from? Were they in your junk box or did you order them online?
I also really like your 40 Meter amplifier. Keep up the good work!
Al, N8WQ n8wq.com
On Mon, 04 Sep 2017 22:00:23 -0400, RCC WB5YYM <curtis03@...> wrote:
Bent the cover today and checked it for fit. I couldn't resist sliding the "junk" over to one side of the bench to see how the home brew station would fit together. I also had an issue with the output jumping up and down, and upon taking a further look, I found the wiper on RV136 only held by the "crimp" on one side. When I touched it, it all came apart. I carefully bent up the side that was originally unattached, placed the wiper back on, and pushed the "crimp" back down. All is good again, and I have it detuned to 1 watt out, to drive the pair of irf510's. Not finished, but getting closer. ?The leaning display is driving me nuts. Got to do some fixing on that. Thinking about duct taping my head over to one side, or possible putting one side of my chair on a couple of books.?
_._,_._,_
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The large knobs are from the junk box. They were given to me by another ham years ago, in a box of small parts.?
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Smitty, N6MTS