Hola from Spain

[ruben]

Hi all


I'm Ruben, 55, from middle nort sunny Spain (Castilla, now are 37º out there...) . So english is not my native language, sorry for any incongruency...

I've put my hands on a radio from about 12 year old, some before to go to the  technical School, late I've done a Eng. degree in electronics (but no many learned here really). Now working in IT.

Yes, I'm  a collector of radios, mainly those that I've repaired when young, and those that saw in adverts and liked in those old years, grundig satellit, Sony multiband, Normende globetrotter, Zenith Transoceanic and so on. .

I've found your forum yesterday, looking for some usefull info about my new summer project, a super regenerative FM radio made with some russian rod valves.

So, I will take a look here, learn a lot, and see if could helpo somebody.

[Murphyv310]

Hi.
Welcome to the forum.
This is a very friendly place and I'm sure there are plenty here that can help you with your projects.

I made a rod pentode VHF FM radio a while back. Here is a youtube clip I made of it. https://youtu.be/toCOwQaBqL0

[Nick]

Hi Ruben and welcome to the forum.

I'm sure that you'll find lots of help for your rod pentode radio here...

[BusyBee]

Hi Ruben, welcome

I have done a little with rod pentodes too and will be very interested in what you do with them. This is one of the best places on the net at the moment for ideas with them.

Tracy

[ruben]

Hi trevor. YEs, I have seen your video on youtube some days ago. I want to made some similar radio. But I believe that yours is a regenerative design, not super-regenerative (may be I'm comfused with this).
On super-regenerative, there are a aditional "quench" oscillation of some kilohertzs that helps to the detection process. 

Hi BusyBee, I have seen too yours post. Very interenting info, for sure.

Hi Nick.

Yesterday I was making wy first testings with a 1J24B valve with low HT voltage (max 31V from my desk power supply), but without any result for now. I don't have any amplification  . I need to check the valve connections and the whole circuit. I think this valve need more HT, so I will try with a 1J29B

I have 10 untis each of 1J29B, 1J24B, 1J18b and 1JP24b. May be could order some 1J37b, those appears to be interesting stuff.

[BusyBee]

You should be getting amplification but it depends on the actual circuit. I built a test circuit without anode resistor and use a resistance box, adjusting for maximum gain. With audio before trying any RF. I have settled on a 60V supply for my circuits as I don't usually use batteries but my power supply which I mostly use has 24V and 35V too. I cannot specifically comment on the 1j24b without looking but most valves give some gain at even 24V. There are differences in the ideal provision of screen (g2) voltage with these in comparison with traditional valve types. I find it gets very confusing with the wire leads as it is so easy to get them mixed up.

Tracy

[henrypal]

Hi Ruben, welcome.

[ruben]

After a valve change I already have found amplification (about 20x), with V+ between 35 and 50V.

I Henrypal. I meet you in some Spanish valve radio forum