Bitx20 V.4


bitx20Bitx20 V.4

Inmiddels is de amateurwereld bij de BitX20 Versie 4 aangeland. Voor wie het niet weet: de Bitx20 is een 20m SSB transceiver met een output van ca. 10W welke geheel uit makkelijk verkrijgbare en goedkope onderdelen is opgebouwd.


Het originele ontwerp is van de Indiase amateur Ashhar Farhan en is door de amateurwereld verder ontwikkeld tot een complete kitversie . De Radio Amateurs Zoetermeer hebben het apparaat twee jaar geleden gezamelijk als project gebouwd (Zie het forum ) en daar een groot aantal uitbreidingen op gebouwd, zoals de digitale frequentie-uitlezing, SWR-meter, S-meter en AGC. En dan is het leuk om één van onze uitbreidingen terug te zien in een nieuw ontwerp: de Bitx20 Versie 4 zoals deze onlangs in de Yahoo Bitx20 nieuwsgroep aangekondigd werd door Elia 2E0ZHN:

"Dear friends and fellow radio amateurs,

I have finally completed my work on the smdBITX, which I called version 4.0 to differentiate it from any other BITX. The smdBITX is based mainly on the version 3 circuit by VU3WJM and the mods and recommendations of Leonard, K0CWOX.

I will be publishing the circuit into the BITX Group very soon, but here is a brief description of what is on the board and what additional features it has:

* The board is designed for all smd components. I have selected 1206 size components as they are relatively easy to solder.
* This board is only the SSB generator, i.e. you will need a BPF, LPF, VFO, PA and a Power Supply to use it. Doing it this way makes it easy to have a multiband BITX or use a set of fixed filters that can be easily swapped.
* There are a few options built into the PCB:
  o There are additional connectors to enable the use of a different Crystal Filter.
  o There are additional traces to allow the builder to use MiniCircuit's ADE-1 mixers for the balanced modulator and the RF mixer instead of the ones built with discrete diodes and toroids. This was put especially for those that hate winding coils.
  o The AGC circuit by PI4RAZ is included on the PCB, the builder has the choice of building it or just bypassing it with the provided solder jumper on the PCB itself.
   o A 78L09 smd regulator for the BFO was added.
   o The BFO has three crystals for USB, LSB or CW work.
* Recently there has been a discussion going on the BITX group pages about the possibility of modifying the BITX and give it a Phasing Mod/Demod. I added on the smdBITX PCB several connectors and jumpers to enable the BITX Experimenters to get the signals they need out easily without having to de-solder any components. A daughter board that piggy-backs onto the smdBITX PCB is currently being developed with space for prototyping the phasing circuits mainly but can be used for any other experimenting work.

This summarizes the smdBITX PCB, I am now working on preparing an instruction manual to go with it and will be publishing it to the files section in the BITX group.

Now for the pricing bit, with the amount of interest I received from you all I can have the boards manufactured and delivered to me at the price of £8.00 (that is UK Pounds). The kit (PCB inclusive) comes to £32.50 (that is UK Pounds).

The delivery charges will vary but will be in the lines of as follows:

* Overseas range between £2.00 and £5.00 depending on country.
* For the United Kingdom it is £2.37 for a recorded 1st Class postage.

Now can I ask you all to re-confirm your interest in the PCB/kit so I can place the order for the PCB's and start preparing the components for the kits please?

Thank you all for your patience so far and hope to hear from you soon,
Best 73's Elia, 2E0ZHN".

En daar mogen we als lokaal amateurkluppie best trots op zijn…