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Technical Topics => Equipment => Topic started by: Exo on September 21, 2018, 0827 UTC

Title: Mod Black Cat Beacon Kit
Post by: Exo on September 21, 2018, 0827 UTC
Here's a theoretically simple, cut-and-jump mod for the existing Black Cat Systems 22 meter Beacon Kit (https://blackcatsystems.com/rf-products/22_meter_band_part_15_beacon_kit.html).
The mod provides operation on a different frequency than originally intended: in the frequency range anywhere from about 80 meters to 40 meters.

Note: This is not an official authorized mod. Black Cat Systems had nothing to do with this mod.

Build and test your original kit first the way it was originally designed.
Then if you choose to do this mod, do it while knowing that it started out working OK.
If you mess up your kit, don't blame Black Cat Systems.
When you do this kind of crazy mod, it is totally your own responsibility
Hams can use this mod for a ham band beacon ;)

With the warnings having been duly admonished, onward to the actual beacon mod:

The oscillator.
It's hard to beat a cheap programmable clock oscillator for simplicity of frequency choice.
Fixed-frequency clock oscillators can also be utilized for this purpose.
A programmable oscillator can be ordered from Digikey or another electronics dealer, pre-programmed to any frequency, or a programmer system can be acquired (http://www.cardinalxtal.com/products/equipment-13) and you can program it yourself.

Theory of the mod circuit:

Theoretical procedure:
1. Remove Y1 crystal.
2. Remove capacitors C4, C16, C17, C18.
3. Remove Jumper at C16.
4. Remove RV1 and put a jumper on the bottom of the PCB in place of it for full power.
5. Do the other cut-and-jump mods around the 74HC02.
6. Remove the L1, L2, toroid inductors and replace with the 2 new leaded 1.5uH inductors in the Low Pass Filter mod.
7. Add the 3 capacitors C3, C8, C9, in the Low Pass Filter mod and leave all the original capacitors in place.
8. Double sticky foam tape the Programmable Oscillator upside down (dead bug style) to the board in the area where the crystal was.
9. Wire the Programmable Oscillator into the appropriate points on the board.
10. Test the unit on a dummy load or ~50 ohm resistor.

Theoretical Parts List for mod version 1d.
QTY, Description, Value
2pc, Inductor, 1.5uH  part link Digikey (https://www.digikey.com/product-detail/en/epcos-tdk/B82144F2152K000/495-6785-1-ND/5209452)
2pc, Capacitor, 470pF part link Digikey (https://www.digikey.com/product-detail/en/murata-electronics-north-america/DE2B3KY471KN2AM01F/490-9543-3-ND/4421252)
1pc, Capacitor, 680pF part link Digikey (https://www.digikey.com/product-detail/en/murata-electronics-north-america/DE2B3KY681KA3BM02F/490-9451-ND/4421255)
1pc, Programmable Oscillator, CPPC4-HT5RT part link Digikey (https://www.digikey.com/product-detail/en/cardinal-components-inc/CPPC4-HT5RT/CPPC4-HT5RT-ND/387814)

Below: Schematic of theoretical mod version 1d.
(http://hfpack.com/members/exo/Black_Cat_Beacon_Mod_v1d_small.jpg)

Below: Large size schematic of theoretical mod version 1d.
(http://hfpack.com/members/exo/Black_Cat_Beacon_Mod_v1d.jpg) (http://hfpack.com/members/exo/Black_Cat_Beacon_Mod_v1d.jpg)

You own it, it is yours to break.
Title: Re: Mod Black Cat Beacon Kit
Post by: Josh on September 21, 2018, 1412 UTC
I don't even have a beacon and I still blame that smolinksi guy.
Title: Re: Mod Black Cat Beacon Kit
Post by: Pigmeat on September 21, 2018, 2157 UTC
You better blame Fansome, too. They're the same guy, ask Pat Murphy and his pal Kracker.

What a couple of jugheads!
Title: Re: Mod Black Cat Beacon Kit
Post by: KaySeeks on September 22, 2018, 0009 UTC
Quote
Note: This is not an official authorized mod. Black Cat Systems had nothing to do with this mod.

Build and test your original kit first the way it was originally designed.
Then if you choose to do this mod, do it while knowing that it started out working OK.
If you mess up your kit, don't blame Black Cat Systems.
When you do this kind of crazy mod, it is totally your own responsibility.
Hams can use this mod for a ham band beacon ;)

With the warnings having been duly admonished, onward to the actual beacon mod:

That's some serious disclaimer activity there.
Title: Re: Mod Black Cat Beacon Kit
Post by: Exo on September 22, 2018, 0025 UTC
Some are probably wondering which beacons are on the air using this mod.
Title: Re: Mod Black Cat Beacon Kit
Post by: Josh on September 22, 2018, 1918 UTC
You better blame Fansome, too. They're the same guy, ask Pat Murphy and his pal Kracker.

What a couple of jugheads!

*Shakes fist in agreement towards shady achers