[BC] trouble with an old BC-1G need advice

[Gary Glaenzer]

" OH AND THE OUTPUT POWER IS 1150 TO 1250 IN LOW AND 2350 TO 2450 IN HIGH"

the 'output power' readings are derived how ?

if it is running ~2600-2700 Ep at high power, your Ip is right on the money

as is your output RF current reading, if into 50 ohms

but no way can those power readings be correct, unless it is running at 153% efficiency


----- Original Message ----- 
From: <BOYDSIRBOYD at aol.com>
To: <broadcast at radiolists.net>
Sent: Wednesday, April 02, 2008 9:01 AM
Subject: [BC] trouble with an old BC-1G need advice


> ok
>
> this is for everyone who has worked on a GATES BC-1G.
> let me tell the sequences of what happened:
> 1. we had a storm 2 weeks ago Saturday in SPARTANBURG,SC, which messed with
> the transmitter.(hold on read on first)
> 2. ended up replacing the RF driver tubes (5933/807's) that brought it back
> to almost normal.
> 3.the following Tuesday was back working on it again, this time i went into
> the atu found a bad pass-through cap either dried up or lighting did one heck
> of  a job on it. i replace it with one that was 10pf higher and took a bridge
> to  check and or retune the atu.
> 4. did a double check on the output cable with the bridge to see if it was
> 50 ohm's and the direct input to the cable. it wasn't so i preceeded to the
> input coil to the atu to bring it to 50 ohm's at the transmitter.
> 5. rechecked the atu with a minor adjustment and found the last two ceramic
> caps had cracks in them and replace with exact values. it all looked good.
> 6. now some may not believe this but; i retuned the transmitter and the PA
> tubes ran real cool in high power. by that i mean that there was little to no
> glow on them. and the owner said someone called him and said he could be heard
>  in HENDERSONVILLE, NC, after all that was done. it ran fine for almost a
> week.(just hold on i'll get to the meter readings).
> 7.it craps out again, this past monday. i worked on it replacing the  RF
> driver tubes and just in case replaced caps 44 and 45 in the output  section with
> exact values. checked tuning and let it go, but the meter values  where
> almost back to the old normal state.
> 8.had to go back on Tuesday and replaced the RF driver tubes just in case
> and found another real bad cap in the PA TUNING section this time. replaced with
>  exact value and checked tuning. he's keeping it on low power until i get
> this  resolved.
>
> NOW FOR THE METER READING IN ORDER.
> 1. for when the tubes ran real cool;   PA PLATE CUR LOW POWER  .3AMPS    HIGH
> POWER .6 AMPS
> RF DRIVER CUR  180MA LOW POWER  175 HIGH POWER
> THE RF LINE CUR  2, 6 AMPS LOW POWER      5  AMPS HIGH POWER
> BASE ANTENNA CURRENT 1 AMP IN LOW POWER AND 2 IN HIGH POWER
>
> 2. AFTER LAST FIX;;;;   PA PLATE CUR  .3 AMPS LOW  POWER   .6 AMPS HIGH POWER
> RF DRIVER CUR  <170> AMPS  IN LOW OR HIGH  POWER
> RF LINE CURRENT 2 AMPS IN LOW POWER AND 4.2 TO 4.4 IN HIGH POWER
>
> 3. NORMAL READING ARE AS FOLLOWS;;
> PA PLATE CURRENT .3 AMPS IN LOW POWER  .6 AMPS IN HIGH POWER
> RF DRIVER CURRENT  175 TO 180 MA IN HIGH OR LOW POWER
> RF LINE CURRENT   2 AMPS IN LOW POWER AND 4 AMPS IN HIGH  POWER
>  THESE ARE FROM THE OWNER AND IF THEY ARE NOT WITHIN THOSE PERAMITTERS  THEN
> SOMETHING IS WRONG
>
> OH AND THE OUTPUT POWER IS 1150 TO 1250 IN LOW AND 2350 TO 2450 IN HIGH
> POWER.
>
> so now for the brain trust what do you think is the problem?
>
> bill
>
>
>
> **************Create a Home Theater Like the Pros. Watch the video on AOL
> Home.
>
(http://home.aol.com/diy/home-improvement-eric-stromer?video=15&ncid=aolhom00030000000001)
> _______________________________________________
>
> The BROADCAST [BC] list is sponsored by SystemsStore - Your Premium
> Supplier Of Components To Build and Maintain A Technical Infrastructure
> www.SystemsStore.com       Tel: 407-656-3719    Sales at SystemsStore.com
>
>
>