Review: Low cost Bitx40 7 MHz SSB transceiver module

Please note that if you add an external VFO and use the onboard local oscillator as a buffer the capacitor to remove is C91 - ie the 1000pF between base and emitter of Q9.

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[Paul_VKHN]

Great review of this quiet little game changer. It represents the ideal first modular prebuilt kit for new or returning homebrewers. That it works out of the box with no alignment or debugging is key. Good-enough quality, immediate operation, ideal power level for making contacts, mod-able and extensible at a remarkable price. I expect to hear dozens, hopefully hundreds of these on air in the next few years. --VK3HN.

[jeromegrzelak]

The 59 dollar one is a gem with the dds vfo putting it into a box is a challange the cal mod is helpfull 4 tuning a great starter rig hope 2 hear every one on the qrp ssb freq kg6mn

[timw]

hi Peter. I emailed you concerning query on a vertical antenna

[kj-cndh]

Hi Peter,

Another great video.  I have one of these, I've put in an external dds as I had people chasing me up and down the band trying to maintain contact before I put it in.  The only thing that bothers me about this circuit now is the loud switching transient that comes through the audio when you push and release the PTT.  I've tried all the mods on the yahoo group but have not found a complete fix.  At the moment I'm waiting on some parts to put together a couple of relays that are controlled by a new "PTT" line.  One relay will control the old PTT line.  The other will switch the audio out line to switch on at the same time as the old PTT line - but switch off with a delay so that transients don't make their way to the speaker. I hate the complexity of this idea, the relays are likely to need some separate power supply circuit and its just not elegant but I find the rig unusable with headphones and mildly annoying without. If you happen to think of something simpler I'd be (very) pleased to hear about it. There doesn't seem much interest in finding a complete fix over at the yahoo group - it seems to be accepted as an unsolvable problem that is an inherent issue of the circuit design.

Regards



Simon
VK3ELH

[timw]

hi Peter. thanks for all your informative videos. can you tell me where in the UK I can buy the BitX 40?

[cbradiohamfan]

Can you please tell me which capacitor I need to remove to make this kit multi banded

Thankyou 🎉


73z.

[cockerspanielhome]

Interesting project, Thanks for the info on this.

[CarstenBauer]

At 5:29 I think I heard my callsign, was this during the 7130dx net on Wednesday Peter? 73 VK6PCB, Portable in the Pilbara, OG97 :-)

[econjack]

Thanks, Peter. Another informative video...as usual. One suggestion: When showing the DDS connection, you point out the inductor to remove, but do not identify the cap to remove. That might be useful.

Jack, W8TEE