Good Es propagation on 4m

Yesterday,  good Es propagation on 70 MHz was present in the direction of Spain and Eastern Europe.

With 10 Watts from my 4 m transverter I made FT8 QSO's with HA5WA, EA6VQ, EC1A and EC1AJL.

Es propagation, May 29, 2020 @ 70 MHz

eQSL confirmation from HA5WA

50 MHz signals from India

When switching off my radio gear yesterday evening I was suprised to find a part of an FT-8 qso from India (QTH loc. JQ05) on my screen !

These were certainly the most distant 50 MHz ham radio signals I ever received:

QSO between VN4VUP and 8U8MBJ on the FT-8 screen.

What kind of propagation must this have been ? Multihop sporadic-E ?

Off topic:

Restoration PSU FP-4

With a rather simple circuit I was able to restore a Yaesu Power Supply Unit FP-4.

The PSU is almost 40 years old and the internal original circuitry was damaged. The transformer, diode bridge and 6800 uF capacitor were still ok.

I found this circuit to replace the existing electronics:

PSU circuitry

Soldered this small circuit on a vero board and installed it in the housing:

Restored PSU

Now the FP-4 PSU is up and running:

Note: PNP Power Transistor MJ2955 may be replaced by MJE2955, TIP2955 or 2N2955.

4 m transverter

With the excellent designs of Serge, UT5JCW ( http://transverters-store.com/ ) I completed a 4m transverter:

The unit operates between 70 ... 72 MHz with IF (from my FT-450) between 28 ... 30 MHz. 

RF output power is appr. 10 Watts.

Although, I do not see much activity on the 4 m band, I spotted some stations operating in MSK144 on 70.175 MHz. Maybe that is something to focus on coming days.

Circuit diagram 28 <=> 70 MHz transverter

Transverter board

Update May 6, 2020 :

Update May 24, 2020 :

First FT8 4m QSO with the transverter over 24 km with PA3EWP.

Update May 27, 2020:

Frequency counter and V/A meter incorporated:

70 cm FT-8 contest

Yesterday evening I participated in a 70 cm FT-8 contest. A good opportunity to test my 28 MHz - 432 MHz transverter.
I was able to make a couple of QSO's (PA3BGQ, PC4L, 2E0NAQ..).

eQSL from PC4L

The QSO with 2E0NAQ over a distance of almost 200 km was very interesting:

70 cm FT-8 contacts March 11, 2020

PC4L, Marcel, sent me an e-mail showing that my signal showed some frequency drift of appr. 10..50 Hz. This is certainly an anomaly that needs to be fixed.

Off topic:

Tulip field near Den Bommel

PA for 70 cm transverter

From BG7SGM, I ordered a PA module for 70 cm:

It is capable of delivering appr. 20 Watts RF at 70 cm. The module uses a M57704H.

I installed the module in the 28 - 432 MHz transverter:

A good heatsink is required. For the first time I used the repeater shift mode of the FT450. For 70 cm repeaters, in The Netherlands the repeater shift is 1.6 MHz. I also had to insert the CTCSS frequency of 88.5 Hz. I made a short QSO with PA0WBS via the Rotterdam repeater (430.300 MHz out). 

A quick measurement showed that the transverter delivered 15 Watts RF. Now, the challenge is to work in digimodes and see what is possible (FT-8 in particular).

See bg7sgm.taobao.com  and eBay for more RF products from BG7SGM (use google translate!).

First FT-8 signals transmitted on 432 MHz

Yesterday I transmitted my first FT-8 signals on 432.176 MHz. PA3EWP received those signals:

At the moment of transmission the 28MHz-432MHz transverter delivered 2 Watts only.

Off-topic (1):

Collection of WO2 communication equipment in the 'Oorlog- en verzetsmuseum', Overloon.

Off-topic (2):

Garden Art

28 MHz - 432 MHz transverter

I started to work on a transverter that converts 28 MHz (10 m band) to 432 MHz (70 cm band). I use a FT450 to process the 28 MHz signals. At 432 MHz the transverter is capable of delivering about 5 Watts RF. A Power Supply Unit from an old PC was used for the 12V/12 Amp and 5V/20 Amp electrical power supply .

Frontview transverter

The transverter and control board I used were purchased in the Ukraine. See http://transverters-store.com/ and also ebay.

                                           Transverter board

Control board with 50 ohms/10 Watt load

First results are promising. I could listen to repeater signals in FM. I hope it will be possible to work with digimodes later on. I will consider adding a PA stage to increase the RF output (to 10..20 Watts).

Kilrock Radio

On Medium Wave I discovered 'Kilrock Radio'. 

They broadcast rock music from the '50-'80s. This is a small radio broadcast station located near Dordrecht. They transmit with 100 Watt RF power on 1287 kHz. I discovered that they can be received on my car radio receiver on various locations in Zeeland and Zuid-Holland. In the evening/night they are often 'overruled' by a Spanish station.

https://kilrock.nl/

Headphone amplifier

The headphone amplifier with VU-meters almost finished:

The pre-amp uses two NE5532 low-noise integrated circuits

https://www.banggood.com/NE5532-OP-AMP-HIFI-Amplifier-Preamplifier-Volume-Tone-Control-Board-p-1098533.html?rmmds=search&cur_warehouse=CN