Search found 726 matches

by Dale H. Cook
Thu Jul 20, 2017 11:07 am
Forum: Everything else
Topic: You need this
Replies: 16
Views: 401

Re: You need this

kkiddkkidd wrote:
Thu Jul 20, 2017 8:36 am
... but didn't find it with a quick search. Maybe someone has a link.
Thanks - I couldn't find it online with a quick search either. I have two pieces of broadcast equipment on the bench at the moment with two more waiting to take their places so I didn't want to invest too much time in the search.
by Dale H. Cook
Thu Jul 20, 2017 8:08 am
Forum: Everything else
Topic: You need this
Replies: 16
Views: 401

Re: You need this

If you've never seen Steve Lampen's demonstration where Belden studied the differences between Monster Oxygen Free 12 GA cable, and "off the shelf" Zip Cord from Home Depot, it's totally worth the time. Is that online somewhere? I'd like to share it with some technically knowledgeable non-broadcast...
by Dale H. Cook
Sun Jul 09, 2017 9:29 am
Forum: Everything else
Topic: Hello?
Replies: 11
Views: 401

Re: Hello?

RGORJANCE wrote:
Sat Jul 08, 2017 4:49 pm
I wonder if that means everything is working fine?
Fossil -

Nope - I have problems at two sites that I'm bouncing back and forth between. Problem is, one is 70 miles west of home, and the other is 60 miles east of home. My bed thinks I'm having an affair with the Explorer and may be right.
by Dale H. Cook
Tue Jul 04, 2017 11:57 am
Forum: AM Radio
Topic: Collins 310W-1 Exciter Divider
Replies: 20
Views: 1099

Re: Collins 310W-1 Exciter Divider

kcbooboo wrote:
Tue Jul 04, 2017 7:33 am
... and can fashion something equivalent, even if on a piece of perf-board.
A previous engineer did that with a 7474, but not very expertly, so I had to revise his work. I want to understand the original design as best I can to insure that the replacement works properly.
by Dale H. Cook
Tue Jul 04, 2017 9:46 am
Forum: AM Radio
Topic: Collins 310W-1 Exciter Divider
Replies: 20
Views: 1099

Re: Collins 310W-1 Exciter Divider

kcbooboo wrote:
Tue Jul 04, 2017 7:33 am
The MC714G wasn't the right chip but it got me into the right section.
The MC713G matches the pinout, but it is a low-power RTL chip so it should be a 3.6 volt chip. I will look through the book and see if I can find a better match.
by Dale H. Cook
Tue Jul 04, 2017 6:29 am
Forum: AM Radio
Topic: Collins 310W-1 Exciter Divider
Replies: 20
Views: 1099

Re: Collins 310W-1 Exciter Divider

That got me to an MC714G. Thanks - I'll have a look at the databook. Of course an exciter schematic would be helpful I have that - it is on the bedsheet print for the transmitter. Later this week (after I patch the tears) I will be getting that scanned and plan to post it with the scanned 820E-1/F-...
by Dale H. Cook
Mon Jul 03, 2017 2:35 pm
Forum: AM Radio
Topic: Collins 310W-1 Exciter Divider
Replies: 20
Views: 1099

Re: Collins 310W-1 Exciter Divider

I am attaching a copy of the 310W instructions manual which has circuit descriptions if it helps. Mark - Thanks for the scan - it is good to have a copy of the manual for the MF exciter, as all I has was the manual for the HF exciter plus the MF print as part of the bedsheet print. I will give the ...
by Dale H. Cook
Sat Jul 01, 2017 8:06 am
Forum: AM Radio
Topic: Collins 310W-1 Exciter Divider
Replies: 20
Views: 1099

Re: Collins 310W-1 Exciter Divider

RGORJANCE wrote:
Sat Jul 01, 2017 7:38 am
I googled the SN1147 and it popped up an LTC 1147/SN1147.
Fossil -

Thanks, but been there, done that. That datasheet is for a step-down switching regulator.
by Dale H. Cook
Fri Jun 30, 2017 5:03 pm
Forum: AM Radio
Topic: Collins 310W-1 Exciter Divider
Replies: 20
Views: 1099

Re: Collins 310W-1 Exciter Divider

You might try seeing if you can find a cross reference to for SN1147. Been there, done that, including digging out old printed ECG and SK cross refs, but I don't have any older than the mid-'80s - the device would have been a couple of decades old (and likely nearly that long out of production) at ...
by Dale H. Cook
Fri Jun 30, 2017 9:21 am
Forum: AM Radio
Topic: Collins 310W-1 Exciter Divider
Replies: 20
Views: 1099

Re: Collins 310W-1 Exciter Divider

Could they possibly be "RTL" ICs... I do not think they are RTL ICs because the crossed-out Z1 voltages in the HF version of the 310W-1 manual are way too high for RTL. All of the RTL that I have seen uses a supply voltage of 3.6 volts. The schematic symbol on the bedsheet shows that they are flip-...
by Dale H. Cook
Thu Jun 29, 2017 10:59 pm
Forum: AM Radio
Topic: Collins 310W-1 Exciter Divider
Replies: 20
Views: 1099

Re: Collins 310W-1 Exciter Divider

awsherrill wrote:
Thu Jun 29, 2017 3:19 pm
In our manual, the part I think you are looking for is called out as SN1147.
Hmmm... I can't get an applicable hit on that part number online, and can't find it in any of my databooks. The chips should be Z1 and Z2 in the exciter parts list.
by Dale H. Cook
Thu Jun 29, 2017 11:07 am
Forum: AM Radio
Topic: Collins 310W-1 Exciter Divider
Replies: 20
Views: 1099

Re: Collins 310W-1 Exciter Divider

I take care of one of these transmitters, but don't know if the exciter manual is still on site or not. Kevin - Did you ever get a chance to look for the 310W-1 exciter manual? I am still trying to figure out what flip flops were originally used. No part number is given on the bed-sheet schematic, ...
by Dale H. Cook
Sat Jun 17, 2017 6:51 am
Forum: AM Radio
Topic: RFI-Resistant USB Audio Interface
Replies: 6
Views: 361

RFI-Resistant USB Audio Interface

An occasional client switched from using a Blue Box in STL mode to a stream feed after installing a cable modem at their 5 kW AM transmitter site. The installation was done by their IT guy who did not understand that an unbalanced output from the computer's sound card might be susceptible to RFI. Ra...
by Dale H. Cook
Fri Jun 09, 2017 4:03 am
Forum: FM Radio
Topic: FM transmitter causing significant hum in surround components
Replies: 9
Views: 554

Re: FM transmitter causing significant hum in surround components

Barnys wrote:
Fri Jun 09, 2017 1:58 am
I am just experimenting in the house.
If this is a house in the United States then you are in violation of Part 15 of the FCC Rules and Regulations. This is a venue for people whose work in part is insuring that the Rules and Regulations are obeyed.
by Dale H. Cook
Thu Jun 08, 2017 4:01 pm
Forum: AM Radio
Topic: Burk ARC-16 ESI Card
Replies: 7
Views: 349

Re: Burk ARC-16 ESI Card

IIRC the ESI had its own manual, but I do not have one in my collection of Burk manuals.