Menu

Marti M-30B

Search this Thread

Prev

Previous Post

Next Post

Next

#2

Report Post

Old

March 13th 10, 08:27 PM posted to rec.radio.broadcasting

John Higdon[_2_] John Higdon[_2_] is offline

John Higdon[_2_] is offline

external usenet poster

First recorded activity by RadioBanter: Oct 2009

Posts: 81

Default

Marti M-30B

In article ,
(Scott Dorsey) wrote:

So questions include: how do I use the switch for tuning, AND once I have
done that, is there any reason not to just leave the switch on TUNE in
order to reduce power and extend the life of the final if I don't mind
the reduced range?

Gee, and I get called an old fogey...I haven't seen tube-type gear in
ages! But seriously, to answer your question: there might be a problem
doing that. The purpose of the "tuning" mode is to limit stage operating
parameters to "safe" levels until proper tuning is either achieved, or
is good enough to allow safe operation of the tube.

You have to ask yourself if the unit, properly tuned, might be better in
terms of efficiency and component longevity in "normal" mode than in the
parameter-limiting "tune" mode. It's a distinct possibility.

Not only that, if I set the antenna coupling for reduced power, is that
going to extend the life of the finals?

It could, assuming you don't kill the efficiency of the output stage.
One of the arts tuning up any transmitting device is finding the sweet
spot in terms of plate current, grid drive, and stage coupling. The
Harris MW-5 transmitters were notorious for having a narrow range of
final plate current and drive. Operate outside that range, and your tube
life drops precipitously, even though from a raw tube-spec point of
view, everything was well within limits.

--
John Higdon
+1 408 ANdrews 6-4400
AT&T-Free At Last

Reply With Quote

Reply With Quote

Thread Tools	Search this Thread
Show Printable Version	Search this Thread: Advanced Search
Display Modes
Switch to Linear Mode Switch to Hybrid Mode Threaded Mode

Posting Rules
Smilies are On [IMG] code is On HTML code is Off Trackbacks are On Pingbacks are On Refbacks are On

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Radio Marti [VOA] on 7405 kHz @ 23:30 UTC	RHF	Shortwave	1	January 8th 09 06:32 AM
Old Marti junk wanted!	Scott Dorsey	Boatanchors	0	July 9th 07 02:25 AM
Troubleshooting Marti STL	Andrew Dickens	Broadcasting	3	April 22nd 04 04:03 AM
Radio Marti A04	N8KDV	Shortwave	2	April 2nd 04 06:13 PM
radio marti question	john hawkins	Shortwave	1	September 17th 03 05:19 AM

All times are GMT +1. The time now is 08:22 AM.

About Us

"It's about Radio"

Contact Us RadioBanter forum home Privacy Statement

Copyright © 2017