50w Marshall without one bell

[Oddvar]

Just a quick one: Can power transformer Hoffman 50w Marshall be sunken into the chassis by taking off one bell?  The chassis is for a combo and I 'm afraid the PT is to heavy to mount on the chassis top itself.  Any advise?

[kagliostro]

If the problem is the weight, leave that bell were it is


Franco

[Oddvar]

Can anyone identify the rectifier diodes he has used her?  JCM800 build;  Can the rectifier diodes be 1000v, 3A f ex?

[kagliostro]

The diodes can be 1000V 3A .... why not ?

Seems they used an old trick adding those rounded pieces of metal with the purpose of heat sink

Franco

[sluckey]

K, there's nothing added to those diodes. What you see is a naked diode. The style is called "tophat".

[kagliostro]

Here someone used to place a small metal sheet at one side of the diodes with the intention it acts as a heat shink

I was not able to read correctly the image so I was confused by that

Now that you ponted to that, they have near the same shape of diodes like the BY100




Franco

[Oddvar]

Nice.  Do they have any advantages over the regulars?

[eleventeen]

Do they have any advantages over the regulars?


Not that I know of, well, maybe they can withstand heating with your soldering iron a little more  than a "normal" diode. That is a form factor that was popular or widely used back when SILICON diodes OTHER THAN teeny 1N34 Germanium diodes first became available. The manufacturers probably perceived that folks who were not used to diodes being able to handle anything in terms of current (eg; used for radio detector use only) wanted to see heat sink, they wanted to see heavy-duty. Remember that there was not especially the need to make everything super small like it is today. When those diodes first came out, most other devices in a piece of equipment were probably tubes. For various reasons, that form factor has persisted. One reason is that those diodes could be mounted in metal clips much like the ones used for mounting fuses to a PC-board. MIL-spec applications usually mounted them that way, for the anti-vibration mechanical strength.


Incidentally, just because that diode is big and metal-cased does not mean that it is high voltage. It has a number printed on it, Google that number and see (and stay within) its specs.


Now we have 1N4007 1000 volt 1 amp diodes in a package the szie of a 1/4 watt resistor. In my opinion, if you went back to 1958 with a 1N4007 nobody would believe you that that little thing could handle 1Kv.

[Oddvar]

Thanks, great answer.