Introduction to UV-K5 HF Fullband receive version 0.3

Introduction to UV-K5 HF Fullband receive Version 0.3

This is an introduction to UV-K5 HF full-band reception firmware 0.3HF using SI4732-A10.

This version is released separately from the existing UV-K5 CEC firmware version. because space is needed to store a large PATCH file to use SI4732-A10's SSB.

0.3HF added several functions to use SSB for shortwave radio and amateur radio.

1. Basic usage

1.1 HF Receive 

Press and hold button '0' (FM radio) to switch to HF reception mode.

Click the Exit button to end. 

1.2 Mode change

In HF reception mode, briefly press F to switch between AM and FM.

(FM broadcasting does not have good reception because an antenna is not connected. However, it is still audible through the connected AM (SSB) antenna.)

Press and hold the 'F' key to switch to SSB mode. In SSB mode, briefly press 'F' to select LSB and USB. The basic usage is the same as Version 2.0.

1.3 Modification example

Below are photos of PA2JSA's modifications.  He sent me a photo and gave me permission to post it on my blog.

It is said that the 3Khz incorrect frequency specified in the picture above was solved by changing the CAP connected to the crystal to 10pF.

1.4 News

Several radio amateurs are designing PCBs.

In particular, we are trying to make DIY easy with PCBs of 0.15mm or less. I can't post it yet because I don't have permission, but I will share my test results in the future.

2.Introduction to displayed items

2.1 In the picture below, item A is the frequency and mode currently being received.

Item B is BFO. 

The SI4732-A10 chip is a low-cost chip ($2~3) that can receive SSB, AM, and FM

However, the minimum frequency change unit is 1Khz

However, it can be adjusted in 1Hz increments by changing the BFO.

I tested this and verified that it also changes the filter passband. If you want to finely change the frequency below 1Khz, change the BFO. You can use BFO as a fine tune. Naturally, BFO can only be used in SSB. The BFO change unit is fixed to 5.

EX) 14.050.080Mhz

      Main Freq : 14.050, BFO 080

2.2 Displays the band of the frequency currently being displayed.

I combined the bands used in conventional shortwave radio with those used in amateur radio. To eliminate empty frequencies, we increased the range of the band little by little, and in the process, it became a little different from the band we know. However, there will be no major inconvenience in using it.

Item A scrolls according to frequency. The underlined part of the band name is the current band. In the picture below 20M is underlined

Item B indicates whether it is a HAM band or a shortwave broadcasting band. There are some errors. (For example, classify the HF CB range as the HAM BAND)

2.3 Signal meter & rssi, snr values

Signal display follows the standard from S4 and above.

Reception exceeding S9 is displayed from +1 to a maximum of +20dB. The maximum is +20dB

3. Frequency change, change of various values

3.1 To change the frequency, use the UP/DOWN buttons as in the previous version.

Starting from the 0.3HF version, the frequency change steps support 1, 10, 100, 1000, and 10000 Khz and are underlined at the bottom of the main frequency.

3.2Starting with version 0.3, values can be changed using only UV-K5's menu button and side switches (two switches below PTT).

Part A refers to the value that changes when the SIDE key is pressed.

When you press the menu button('M'), the selection changes as shown below.

The current value of the selected item is displayed below.

In the picture below, the BAND item is selected and the current value is 20M band.

In the picture below, part A currently displays each item.

I put it in small letters because it's not that important. If small letters are difficult to read, press the M button and look at the bottom line. 

For example, let's change the steps.

Press the 'M' button to change the selection to STP (STEP)

Currently it is 1Khz.

Press the side key UP to change to 10Khz

For example, let's change the band.

Press the ‘M’ button to select BND (BAND)

Current Band is 630M

When you press the SIDE Down button, the band below it, L.F., is selected. (I don't think anyone uses it and I have never used it, but since SI4732-A10 supports it, I added it to the band)

You can move to the desired band by pressing the SIDE UP/DOWN keys as shown in the pictures below

3.3.Todo

Only some of the values set by the user are saved in eeprom when the user exits by pressing the Exit button. This is because integration with other versions has not been decided.

If the address of the eeprom to be used is determined before Version 1.0, most of the values selected by the user will be saved in the eeprom.

4.Video

5.Download

Download and use CEC_03.HF.packed.bin from the link below.

https://github.com/phdlee/uvk5cec/releases/tag/v_01HF