Special Topics relevant to Project Pages
On my project pages reference is made to more general topics considered important in the context of the work described. To avoid repeating e.g. thoughts on solid tantalum capacitors, such comments are summarized under this heading "Restorer's Notes".
Additional topics are discussed and described in my articles in club magazines found in → Publications.
To read the HTML or PDF texts, just click on the title links marked with a → .
Recently I wrote an article in HISTEC Journal discussing analysis, construction and use of adapters for such overpriced tubes in home radios. These procedures could well be used in other applications as well.
EL11 and intelligent adapters using 6T10/6AD10, 6HB6 and 6BK5.
This note describes the problems and failures encountered in equipment using these components and indicates solutions.
- → Care of Series-Parallel Filament Circuits, Part 1: Indirectly heated tubes
- → Care of Series-Parallel Filament Circuits, Part 2: Directly heated tubes
These notes describe the checks and measurements required when servicing or modifying radios that utilize series-parallel heater circuits for indirectly or directly heated tubes and dial lamps such as found e.g. in many military or aircraft radios or Collins or Heathkit ham gear.
A lot of damage has been caused by inserting transmitter tubes stored as spares or bought as NOS directly into the transmitter sets without first passing a much needed reactivation process. Various authors have added helpful explanations and practical tips to solve this problem.
All too often drop type tantalum capacitors used in military and commercial equipment fail, usually shorting the supply voltage. Here an explanation for the cause is given and potential solutions for replacing them are proposed.
Many a set or power transformer has been damaged by old electrolytic capacitors presenting a very low impedance or a short to the power source. Long storage alters the chemistry inside these units causing this effect. The capacitors therefore have to be replaced by new units (best solution), by reformed NOS units or carefully reformed - if possible. An internet search will provide many interesting links covering this matter - A selection is shown on the left: "Special Links".