YouKits HB1A – Replacing the LCD module

With my plans for minimalistic, CW only, RaDAR activities I managed to swop unused equipment for a YouKits HB1A 3 band (40m/30m/20m) QRP trail style radio but needed to give the LCD screen some attention. I considered this to be “bonding time” between myself and the rig. There is not much information on the Net so I decided to document the steps I took to do the replacement an operation that took a nerve racking four hours to do.

I needed to remove the back cover, the control knobs, the PCB retaining screws (2 of) , the nut and screw holding the power transistor in place for heat sinking and also the coax connector.

The module’s connector pins needed to be unsoldered (12 of them) but it was a mission and using a solder sucker didn’t help at all. This is generally a difficult operation as many of us will know.

I was hoping for a dry joint somewhere although the symptoms didn’t agree but I tried anyway as a first line repair without success.

I had to eventually use my Dremel drill with milling bit to cut the module away and use a sharp wire cutter to remove the left over PCB sections from the pins.

I had some coffee before continuing.

The pins needed to be cleaned before they could fit into the holes of the new LCD module. I also used a scribe to try and slightly increase the wire holes sizes on the LCD module thanks to a suggestion by my friend Daryl ZS6DLL. I soldered them lightly into place (Thinking of the next guy that may need to unsolder again one day!!!)

I was wary of applying power but things need to be done and I was relieved to see the new module worked!!!

Unfortunately, once all was reassembled the rig wasn’t putting out any power and not receiving any signals either. But, that’s for the next bonding phase. Fortunately this is a rig that can be repaired by yourself with a little patience and ingenuity, lots of patience!

I suspect (hoping) the problem lies in the vicinity of the BNC coax connector …. I’ll need to redo the PCB to connector connection using a short flylead.

SMD devices are so tiny but fortunately it wasn’t necessary to go to that level, not yet anyway.


The RX / TX problem was caused by a damaged L4 inductor that was damaged during the LCD replacement, a tiny scratch on the component.

If you zoom in on the picture you can see it. (Top left) I temporarily replaced it with a 1.1 uH inductor and the receiver was it’s awesome self again!

Hope someone finds this information helpful one day!

73 de Eddie ZS6BNE

4 thoughts on “YouKits HB1A – Replacing the LCD module

  1. A good suggestion is to keep a roll of solder wick, a type of braid used for absorbing solder when removing surface mount components. It is 10 times better than a solder sucker and it would have made the job easier.
    As for the next step in the repair, I am confident you will trace the missing signal… Remember my note to you – take voltage readings on the first mixer, these little guys become deaf when that goes south…

    Good luck and I am looking forward to hearing the HBA1 soon… Will work you with my one…


    • Looking forward too Kevin!!!

      Yep, I scrathed L4 in the process damaging that little inductor. I replaced the 2.2uH with a 1.1uH … not sure of the effect but everything is now operational. Not sure how much power is being put out exactly either.

  2. Pingback: RaDAR – Another interesting L-Match designer – ZS6BNE's Blog

  3. Hi Eddie, I know this post is three years old, but could I make a couple of remarks: On the damaged inductor, it looks like that wire was merely nicked during the removal of the display. Could you not have simply repaired it with a spot of solder? From the photograph, it looks like that would have worked.

    I found your blog while looking for information on how to mod these HB1A rigs to make them transmit on three bands. Apparently, they came out as TX capable on only two bands. Mine is an early one and does tx on 20 and 40 meters, but I have seen reference to a simple mod that makes them tx on 30 meters also. Can you reference any links to that mod? I can’t find any.

    Glad you got the little radio fixed anyway. Solder wick is good by the way. Might have avoided the dremel. I have had some horrible results from mechanically trying to desolder. Wick and flux is the best way I think.


    Tony G0BZB

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s