Category Archives: Uncategorized

Repeater Update – More damage!

Repairs were started a few weeks ago on the lightning damage to the repeater, and it is far more extensive then I had originally thought.  The lightning did come in on the AC mains, so measures are being implemented to prevent this in the future…

Overall, the only component that does not seem to be damaged is the old MCC RC-100 controller. Here is the damaged item list:

Receiver: blew the LM386 amp for the external speaker.
Exciter: shorted Q4 in the amplifier stage
TS64 CTCSS Board: unknown damage, no longer encodes tone
AP50 Audio Board: destroyed the reverse protection diode and filter capacitor on the power input lines
Power supplies: Both the 12V and 24V power supplies suffered damage

The exciter and receiver have been repaired, and are functioning correctly and well within specs. The AP50 audio board was also repaired, however I will not be putting this back into service, details below.

With the amount of damage done, I figured it’s time for an upgrade to the system. I’ve removed the controller, TS64, and AP50 and will be replacing them all with a Raspberry Pi based controller. Also, I am rebuilding the amplifier to run on 12V instead of 24V. This will make it less cost prohibitive to install a battery back-up, and also easier to maintain.

Parts have been ordered, and repairs will resume shortly. Stay tuned for further updates.

 

 

Update: Repairs started

Update: Finally got a chance to work on the repeater. Thankfully, the damage was minimal!  The lightning hit the receiver, CTCSS board, new audio board, and possibly damaged the EEPROM on the controller. The only component damaged on the receiver was the LM386 for the external speaker (which isn’t used anyway). The damaged part was removed and the area cleaned.

On the audio board, the lightning took out the reverse protection diode, and filter capacitor. Both of these items were removed, areas cleaned, and new component installed.

The CTCSS board appears to have no damage, but it no longer decodes or encodes tone. A replacement will be ordered.

As far as the controller goes, it still has the CWID on it, but does not respond to any DTMF commands. Even a force reset does not work. We will investigate further, and either repair the existing controller, or perhaps look for a replacement.

Stay tuned for updates!

 

 

 

 

 

 

 

 

 

224.580 Down

lightning_strikes_tower_header

During the storms last night, we suffered a lightning strike. Initial observation was 147.105 running on batter power, and 224.580 completely off the air. Upon arrival at the site this morning, all circuit breakers were tripped, and the back-up battery for 147.105 was dead (repeater turned off at low voltage level). Breakers were reset, and systems came back up. However, the audio on 224.580 was non-existent. A quick inspection showed burnt parts on both the receiver and the new AP50 audio board. The repeater was removed from the site, and repairs will commence as soon as possible.

Updates will be posted to keep you all up to date.

 

Repeater repairs and upgrades

The 224.580 repeater had been repaired, and is back online. The power amp failed finally, and was somewhat repaired to get it back online. Three of the 5 FETS are dead, so those circuits were removed and bypassed. The amp is putting 20 watts to the feedline, better than the 1.5 watts from the excitet.

The upgrade is to the audio. Since this repeaterhasd been on the air, I’ve never been happy with the quality of the audio. I’ve finally reworked it, and it sounds great! We are now passing “flat” audio thru the system. Give it a try and let me know how it sounds.

Work continues on the next 220 repeater.I’m hoping to have it somewhat on the air for testing soon…