Pre-Assembled Boards: OLED V2.2 / Mainboard V2.6 / RF Board V3.1

This Version is only available from commercial sellers. Gerbers of this Version have not been published.

Changes OLED-IO Board:

Diodes 1N4148 are now SMT, and factory assembled

Changes Mainboard:

20MHz / 27MHz Crystals now SMT and pre-assembled
Diodes 1N4148 are now SMT, and factory assembled
7805 is now SMT and factory assembled
Q1 (BS170) is now SMT and factory assembled

Here´s the Information you need to complete the Rig.

Let´s start with the modified iBOM´s. Every Part that´s already on there, is checked as sourced and placed (exept for the changes above). The Amount of remaining components to source can vary over time. It depends on availability of Parts at the Supplier.

So you just have to take care of the Rest.

Explaination / How to use: The iBOM is a (downloadable) interactive html-file, that shows you which component goes where. It is helpful, to keep track of what you are doing. Schematic is also available as reference and sometimes contains some additional information.

For critical parts I´ve tried to provide a link to the related item in a shop (either reichelt or mouser) Those are no affiliate links. They are just thought as help for you, to get the right parts !

When it´s sold out at that vendor, you need to look for other sources. But at least you know the exact Part, you need to look for.

OLED IO-Board:

BOM_uSDX-Sandwich-IO-Board-OLED-checked

You just need to source and place the THT Components.

Here´s the Schematic for the OLED IO-Board: Schematic_uSDX-IO-OLED_Rev2_1

Notes:

SW4 (rotary encoder) use EC11B13 (Unlike other rotary encoders, this one is known to work without trouble and comes at a reasonable price)

SW1-SW3 you can use for example these

MK1 (on-Board Mic) for example this one (watch for polarity !!!)

J4,J5,J6 use these

J1 and J2 are male jumper connectors, nothing special

J3 is Place Holder for OLED Display, like this one (if you buy another one, watch for the right order of the Pins)

J7 and J8 are Female Pin Sockets, with bent contacts for horizontal mount. Nothing special.

From here on, using the old 2.1 Pics and descriptions, as nothing has changed….

This image has an empty alt attribute; its file name is comp_20201228_155116.jpg — (Almost) everything placed on the Top Side

This image has an empty alt attribute; its file name is comp_20201228_161449.jpg — Here I prepare a Socket to Plug in the OLED

This image has an empty alt attribute; its file name is comp_20201228_161552.jpg — I´ve shortened the PINS of the OLED Display, so they will fit in flush.

This image has an empty alt attribute; its file name is comp_20201228_162432.jpg — OLED Socket soldered, and Inter-PCB placed and soldered

This image has an empty alt attribute; its file name is comp_20201228_162848.jpg — For the programming Interfaces, I use left overs of the long Adafruit Male/Female Stacking headers (See Mainboard for Details). I cut them to required length, bend them and solder them in.

This image has an empty alt attribute; its file name is comp_20201228_163409.jpg — Last thing is the rotary encoder. Now the IO Board is ready

This image has an empty alt attribute; its file name is comp_20201228_163140.jpg — Bottom View

Mainboard

BOM_uSDX_Main_Rev2.5_4Layer-checked

You just need to source and place the Si5351 and the FST3253 SMT IC´s and the THT Components. JLC-PCB do not have the IC´s in Stock and cannot place them for us.

Here´s the Schematic of the Mainboard:Schematic_uSDX_Main_Rev2.5_4Layer

Notes:

U4 is 74ACT00 in DIP-14 Package

U6 is ATMega 328 in DIP28 Package use Socket for that

U3 is LM4562 in DIP-8 Package

U5 is Si5351 in MSOP-10 Package

U1 is FST3253 in TSSOP-16 Package

J2 and J3 are cut from Male/Female Stacking Header Set

J1 is Terminal Block by Phoenix Contact, can be replaced by anything with5,08mm Pin-Spacing

Start with soldering U1 and U5 on the pre-populated board.

Here are some Tips, how to solder those small IC´s without special Tools:

All that´s left on the SMT Side is bridging R22:

I used 0 Ohms Resistor on Position of R22- you can use a cut of wire, or even a solder blop.

Next, we place the THT Components… Pretty self explaining

Following pictures are from old Revision, but the Task is the same:

This image has an empty alt attribute; its file name is comp_20201228_173825.jpg — Next, I cut off 2 pieces of a 36Pin Stacking Header at the 15th Pin. This Pin will be lost.

This image has an empty alt attribute; its file name is comp_20201228_173950.jpg — Left: fresh cut at 15th Pin / Right cleaned up a little towards 14th Pin.

This image has an empty alt attribute; its file name is comp_20201228_174350.jpg — Then simply solder them in

This image has an empty alt attribute; its file name is comp_20201228_174609.jpg — After you´ve put the ATMega in the Socket, the Mainboard is ready. (You still need to screw in Power Supply cable and Program it later)

8-Band RF Board

Will be dealt with on the Main Page of this Board.

8-Band RF Board

Opposite to this instructions it can have the GPIO Expander, the PA Fet, the blocking capacitors and the Pull-Up Resistor installed.

Software

is expained here

In case, you still hear noise from OLED (change in Noisefloor when you unplug OLED)

Try another ATMega. Sounds stupid, but I had the case, that one ATMega would create audio humm (from OLED) the other not. Seems, like there is also Tolerances involved in their ADC Quality….