ITT teddy 4 came as not working together with another radio I bought from an ebay seller. This radio is from early seventies, I estimate.
The radio is medium-sized, not a small one, but also not a large one. Sound is quite impressive, it has more bass than I expected. Sound, compared to e.g. ITT Junior automatic, is much better.
This picture was done after repair and cleaning all caging parts.
I wanted to replace a 4x1,5 volts baby cells power arrangement in an old radio ITT teddy 4.
New battery should be the ubiquitous 18650 cell. It offers about 4.2 volts, so I looked for a solution that does up conversion to about 6 volts, and that offers a USB connector to load the cell.
Best would be to have also some battery protection (undervoltage protection, current overload protection).
I found two interesting modules for further analysis.
This is a great DMM from the around 1979.
It is called “Microvolt Digital Multimeter” because it has a resolution down to 1 microvolts. Even more interesting is the current range, going down to 1nA (nanoampere) resolution.
This is due to the DC range 20 mV (20.000mV) and DC current range 20 µA (20.000µA). Finally, it has a 1mOhms resolution on 20.000 ohms range.
This multimeter is great to measure small currents, e.
HP 6111A DC Power Supply is a precision power supply for 0-20 volts and 0-1 ampere current. It has a 5 digit digital input to select the precise output voltage. The HP611x is a whole series of such PSUs with different output voltages.
I have also a HP6112A, going upo to 40 volts. See here for details on that other PSU.
This is a device from the 60ies or 70ties. I could not find any date code for my device.
Some tweaks to make OpenSuse work as expected. This was done with version 15.4 but usually these topics are to be done for every new version. I list them here to not forget how to fix the issues.
Make dmesg work dmesg does not work for non-root users, it needs a tweak to do this.
sysctl -w kernel.dmesg_restrict=0 bash -c 'echo "kernel.dmesg_restrict = 0" >> /etc/sysctl.d/10-dmesg-non-root.conf' See https://forum.ubuntuusers.de/topic/schikane-mit-dmesg/
Make external soundbox work via bluetooth This is another ugly story.
Some remarks to set up an existing empty OpenSuse Leap notebook (HP Elitebook) for FT8.
I started with HamPI on a Raspberry for the same task, but I did not like the many parts flying around on my desk (Raspi, small monitor, mouse+keyboard, powers supplies for all, active USB switch). So I decided to replace this solution with an older HP Elitebook 840 G3.
To not rely on available/non-available packages, I usually build all the tools from source.
Trapider TE-15 Grid-Dipper.
Frontplatte mit Frequenzeinstellscheibe, Anzeigeinstrument sowie Frequenzeinstellknopf und Ein/Aus- / Empfindlichkeitsregler: Originalverpackung nur in Teilen vorhanden. Man sieht das Gerät, Spulen für die unterschiedlichen Frequenzbereiche sowie Ohrhörer und Anleitung. Zwei der Spulen, hier für 40-140 Mhz und 120-280 Mhz: Das überschaubare Innere: Transistoren 2SB422: Hier eine Germaniumdiode: Ein Scan der Anleitung: Das Gridmeter in Nutzung. Es ist eine Frequenz von 700 Khz eingestellt. Die Meßspule liegt direkt über einer Spule eines Testaufbaus (Meissner Oszillator).
Morsetasten HI-MOUND Manipulator MK-706 Japanisches Double Paddle für Squeeze Keying. 950 Gramm Gewicht
Junker M.T. Patent von 1931. Seit 1934 in Bad Honnef gefertigt.
Meine Taste ist “Ausführung Bund”, also für die Bundeswehr gefertigt. Im Vergleich mit anderen Tasten würde ich die Taste als nach 1960 einordnen (aber wissen tu ich nix).
Siehe auch https://de.wikipedia.org/wiki/Junker_Morsetaste_M.T.
See https://stackoverflow.com/questions/64050359/how-to-use-markdown-syntax-to-write-math-in-hugo or here : https://bwaycer.github.io/hugo_tutorial.hugo/tutorials/mathjax/
Add these line
<script src="https://polyfill.io/v3/polyfill.min.js?features=es6"></script> <script id="MathJax-script" async src="https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js"></script> To the layout file of your hugo template. I use theme mainroad, and added the lines in themes/mainroad/layouts/_default/baseof.html, in head-section of html.
Tests $$f_{res} = \frac{1}{2\pi\sqrt{LC}}$$
This shows as Mathjax \(a \ne b\), but this doesn’t (a \ne b)
Likewise, this shows as Mathjax
\[a \ne b\]
but this doesn’t:
[a \ne b]
$\sum_{i=0}^n i^2 = \frac{(n^2+n)(2n+1)}{6}$
The M8047 MXV11-A Multi Purpose Card board has DEC Boot PROMs, two sockets for up to 2x4 KBytes. I tried to read the data on these >40 years old EEPROMs.
For the two PROMs on the board, I could find the DEC part numbers 23-03901-00 and 23-04001-00 on them, which are 6341 Chips with 512x8 Bytes each. These ROMs are MXV 11-A2 Boot ROMs for RX02, RX01, or TU58
With My Batronix Barlino II Eprommer I was able to read out both ROMs (more info on the Eprommer see here.
