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Old 22nd Jun 2021, 11:35 pm   #81
Jolly 7
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Default Re: Mini-Mod 2021!

Quote:
Originally Posted by technotel View Post
Hi Jolly
I have someone already requested it although he was going to send payment for postage, he hasn't done so yet. So give it a little longer and I will get back to you. He may have decided he doesn't want it after all? So you will be next in line.
Terry
Thanks Terry.
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Old 8th Jul 2021, 10:58 am   #82
fastpete
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Default Re: Mini-Mod 2021!

Here are a couple of pics of my Mini-Mod 3d printed enclosure. Not as period correct as some of the other beautiful boxes here but it's nice and low profile.

HERE is a link to anyone wanting to print their own.

I can't get over how well these work. They really bring a new lease of life to these radios. Particularly in Ireland where there are few AM stations left.

I have 3 more to build!
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Old 8th Jul 2021, 11:39 am   #83
Ian - G4JQT
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Default Re: Mini-Mod 2021!

It's really good to see that this project is still living. I wrote the MiniMod article that got published in the BVWS Winter 2011 edition!

It always was a compromise between complexity and performance. Great to see the variety of enclosures and the efforts made to make them - I just used plastic project boxes from ebay.

As stations continue to close, it's possible Ofcom will be even less likely to take an interest in what's going on in medium wave - as long as a station's content doesn't draw complaint.

(I was told unofficially in 2014 by an Ofcom inspector that MW pirates are no longer on their radar, as long as the content isn't political, racist, etc. and that would only come to their attention by a report from a member of the public. Our pantry transmitters put out less energy than many SMPS, and don't cause wide-band interference. Nevertheless, unofficial broadcasting is still illegal.)

In future I may develop a simple, more stable and effective AM signal source using CPP Field Programmable Blank Oscillators. They are MUCH cheaper then quarts crystals!
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Old 8th Jul 2021, 1:58 pm   #84
Electronpusher0
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Default Re: Mini-Mod 2021!

I agree that its good to see the minimod still going strong.

Depending on demand I may be tempted to obtain and offer more boards at some time.


Quote:
Originally Posted by Ian - G4JQT View Post

In future I may develop a simple, more stable and effective AM signal source using CPP Field Programmable Blank Oscillators. They are MUCH cheaper then quarts crystals!
If you need a pcb laid out on Kicad just let me know. - FOC of course, least I can do.

Peter
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Old 9th Jul 2021, 8:59 am   #85
Pamphonica
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Default Re: Mini-Mod 2021!

As a small minimod mod, I have experimented with a tiny twin gang cap, about 20pf per side, in parallel across the two main (270pf) caps, but reduced those to 220pf. This allows a small swing, about 30kHz, just enough to get rid of birdies and interference on some sets. I’ll report back once I’ve used it for a bit.
The cap was NOS but was probably designed for a small vhf only set. Nice metal framed air spaced job, with a built-in 3:1 drive. Only about 20mm across.
-Jeremy
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Old 3rd Sep 2021, 2:17 pm   #86
Telegraph-Hill
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Default Re: Mini-Mod 2021!

Hello lovely people, I am a Radio Presenter since 1992 and do my German shows via Internet for the last 10 years. I am also into electronics and all the studio gear I am using.

I just want to make a show sounding like the real 60s. All affords to use EQ's are not really successful. The best sound I got out of an Leak30 Amp. They are using very good high filters to get rid of the hiss from the old 78's.

My plan was to get 2 Broadcasting systems running using either one of the one discusses in this thread and 2 receivers (I have some brill hacker units here) to push the original stereo signal coming out of the mixing desk into 2 Mini-Mod's (one for each channe) and receiving by my hackers.

In Theory I do not need a long areal. I was wondering about the interference from this setup as I broadcast 2 different frequency's.

What do you think?
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Old 4th Sep 2021, 10:57 am   #87
Ian - G4JQT
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Default Re: Mini-Mod 2021!

The MiniMods are designed to have a range of only a two to three metres. This keeps them legal for those who are nervous of being accused of operating an illegal transmitter. But of course the range depends upon local noise, channel occupancy (you'd choose a clear one anyway) and receiver sensitivity. Extending the MiniMod radiating aerials works to some extent, but if too long it will detune the output tuned circuit unless you change the fixed capacitor.

I don't think they will be suitable for your application. Nevertheless, having two low-power around-the-house MW transmitters on different frequencies shouldn't present any problems. I've built various transmitters to serve more than just my house and had them all operating without any problems. Just ensure that they are more than three or four channels (at least 27kHz) apart.
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Old 6th Sep 2021, 5:56 pm   #88
rambo1152
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Default Re: Mini-Mod 2021!

Quote:
Originally Posted by Telegraph-Hill View Post
My plan was to get 2 Broadcasting systems running using either one of the one discusses in this thread and 2 receivers (I have some brill hacker units here) to push the original stereo signal coming out of the mixing desk into 2 Mini-Mod's (one for each channel) and receiving by my hackers.


What do you think?

Are you going to mic the Hackers like guitar amps, or take a direct audio output?

Either way I don't think this is the way to create an authentic '60 sound unless you want everything to sound like "The days of Pearly Spencer".


There must have been more to studio audio processing in the '60s than just EQ, what about dynamic compression?

Were the 60s pirates using Orban Optimods? what was being used before those?

Luxembourg sounded very "bright", and I'm sure there was some reverb added too, perhaps that is the definitive sound of '60s AM radio?
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