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I would replace the LM386 they are relatively cheap, only issue may be time waiting to get one through the mail. If you have another audio amp, you could try connecting the wiper of the volume

Iz I suspect the inductor I used from coilcraft is at least as good as those in v5.? Q ~ 60 or 70 above 45 MHz.? I am contemplating a BPF based upon a T37-6 and a cap, but since we need rejection

I can try that on the short patch from tuner to meter or radio as I have LM240 there. but the line going to antenna is RG213. So I don’t have a clip ferrite that big.

I had similar problems when connected to an off center fed dipole.? i solved my issues with clip on ferrite on the coax going to the antenna.? That may work for you.? Maybe a ferrite between the

Hi Evan, Following your recommendation, I disconnected the 12V, 3A AC->DC powersupply and replaced it with a 12V battery. The humming noise is now gone but I can still not hear any of the signals

Hi Sam, I had a pvc air wound one too. 21ft of coax, but it was some real crappy coax so I took it off. I will try a better one. I was eyeing an inline choke, I was thinking of getting the my

Curt, is your ineffective LC 45mhz filter the same you find in ver5? Have you used toroids? Which color or which inductors have you used? Il 11/apr/2019 16:03, "Curt via Groups.Io"

U have a choke on the efhw? I have a very similar set up and run into similar issues without one. I use an pvc wound coax choke.? Or, try adding/removing a couple feet of radiator line? Intermittent

You must have quite the high-end Spectrum Analyzer if it can accurately measure to 0.2db or less at that level… and NIST calibrated to boot? Ours are only good to 0.8dB… Sent: Thursday,

Hi, So I made some progress with adding the diodes on the RX and TX blocking the discharge of the caps near by. And I was able to get the CW key to stop sticking with a .01uf on the blue line to

Drawing lotsa current from supply, the ripple will increase ..more ripple, more hum Jim

With no antenna, the uBitx should be very quite.? If you are getting the hum without the antenna, I would start with the LM386.? Inject an audio signal in to the volume control wiper to see if that

I disconnected the TX PA part of the uBitx (brown wire) in order to test RX in isolation. Results: Unfortunately receiving is also no longer working. Tuning across the 20m band results in a uniform

What Arv is suggesting sounds pretty much the same as setting the IRF510 PA bias? as per step 1 of Farhan's tuneup instructions:?http://www.hfsignals.com/index.php/ubitx-tuneup/ If you can adjust

Power is always applied to the finals, Tx or Rx. In Tx the bias supply is activated, which, through the bias pots, biases the MOSFETs up to the idle current. If the FETs are heating in Rx it’s

Your welcome Curt, I had to do the math for myself too.? I have not done any hardware modifications as yet, only non-stock thing is KD8CEC firmware.? AGC add on from N8DAH is next (working on it

I would recommend this device: https://www.amazon.com/gp/product/B01H6QKVOU/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1 ? Clones can be bought through eBay for less. It has worked for me

Should be possible to test the IRF510 devices. In-circuit testing is a little more complex but testing them out of circuit is relatively simple. Out-of-circuit tests might just involve a 1K resistor

You might have a connection problem too. Disconnect the computer interface. The display should show TX if power is being applied to the finals.

Now you will be a radio doctor... ?