Previous in Forum: Generator Protection in Neutral and Line   Next in Forum: Under Voltage Problem at DG Sets
Close

Comments Format:






Change Mode
Close

Subscribe to Discussion:

CR4 allows you to "subscribe" to a discussion
so that you can be notified of new comments to
the discussion via email.

Close

Rating Vote:







Add Vote
9 comments
Rating: Comments: Nested
hydrogenhead
Power-User

Join Date: Jan 2011
Location: Scotland
Posts: 361

Increasing RF Modulator Power

12/02/2012 12:10 PM

Is it possible to modify an RF modulator to give out higher RF power? I have one from a Playstation 2. I can get a range of a few cm from it but I was wanting a few meters. Are there resistors that can be removed?
Register to Reply
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Good Answers:

These comments received enough positive votes to make them "good answers".
3
RAMConsult
Guru
Engineering Fields - Power Engineering - New Member

Join Date: May 2007
Location: NYC metropolitan area.
Posts: 3230
Good Answers: 444
#1

Re: Increasing RF Modulator Power

12/02/2012 11:16 PM

Probably not. You're assuming that the resistors are somehow limiting the output signal, they're not. RF modulators do not have a typical RF amplifier output stage with tuned circuits to couple the RF energy to an antenna. Instead they are intended for direct connection to the input stage of a tuner that expects only microvolt/microwatt signal levels from an antenna, therefore their output power is commensurately much lower than broadcast strength.

You could buy a linear RF amp and run the modulator through it to an antenna, but by the time you go through that expense it would be much cheaper to buy one of these. I hope you enjoy all the email that they send you.

__________________
 “Tell me and I forget. Teach me and I remember. Involve me and I learn.” Ben Franklin.
Register to Reply Good Answer (Score 3)
No more Good Answers.
caeser
Commentator

Join Date: Aug 2012
Posts: 68
#2

Re: Increasing RF Modulator Power

12/03/2012 9:54 AM

No you can't but you can feed the low RF modulator signal to an RF power amplifier stage with same frequency of the modulator and the same output impedance (50 OHME) the stage (circuit) consist of one transistor called booster .
Register to Reply
ci139
Guru

Join Date: Feb 2012
Posts: 595
#3

Re: Increasing RF Modulator Power

12/03/2012 10:15 AM

( ( (( [YOUR DEVICE] )) ) ) ~ ~ ~ ( ( (( [Bi-Di RF Antenna] )) ) )

This is the external standalone module to be added

Hi-Fq signals are easy to shift to another Fq just by setting the device to consume more(/less) power from what it's designed to ... ec. ec.

__________________
 ci139
Register to Reply Score 1 for Off Topic
leveles
Guru

Join Date: Jan 2008
Posts: 1753
Good Answers: 59
#4

Re: Increasing RF Modulator Power

12/03/2012 8:22 PM

Yes, You Can!!

By reducing said resistors the reach increases, and its life expectancy decreases.

Use it sparingly (1% duty cycle, 10microsec bursts each), and your reach might be increased 10 - 100 fold. Please contact radar specialists for details.

And worrying about exceeding FCC limits? You will find it out in due time. Why worry, before the so-called due time comes?
Register to Reply
hydrogenhead
Power-User

Join Date: Jan 2011
Location: Scotland
Posts: 361
#5
In reply to #4

Re: Increasing RF Modulator Power

12/04/2012 6:05 AM

I burnt out the ps2 modulator. I tried again with an old Astec modulator and I managed to get much more power. The signal was appearing at around 580 Mhz and I could get a strong signal from the other end of my room. There is a resistor that I can lower the value of for even more power.
Register to Reply
RAMConsult
Guru
Engineering Fields - Power Engineering - New Member

Join Date: May 2007
Location: NYC metropolitan area.
Posts: 3230
Good Answers: 444
#6
In reply to #5

Re: Increasing RF Modulator Power

12/04/2012 11:45 AM

Good for you. Please post when you burn out that one too!

__________________
 “Tell me and I forget. Teach me and I remember. Involve me and I learn.” Ben Franklin.
Register to Reply
hydrogenhead
Power-User

Join Date: Jan 2011
Location: Scotland
Posts: 361
#7
In reply to #6

Re: Increasing RF Modulator Power

12/04/2012 3:03 PM

It still works and can now transmit through the whole house. It does not even heat up in the slightest.
Register to Reply
caeser
Commentator

Join Date: Aug 2012
Posts: 68
#8
In reply to #7

Re: Increasing RF Modulator Power

12/05/2012 9:55 AM

Why it is working right now while the others have been burned??.
Register to Reply
hydrogenhead
Power-User

Join Date: Jan 2011
Location: Scotland
Posts: 361
#9
In reply to #8

Re: Increasing RF Modulator Power

12/06/2012 1:23 AM

Because it is a much older design which does not use an IC for the modulation. I believe a colpits oscillator is used.
Register to Reply
Register to Reply
Have a Different Question?
9 comments

Good Answers:

These comments received enough positive votes to make them "good answers".
Copy to Clipboard

Users who posted comments:

caeser (2); ci139 (1); hydrogenhead (3); leveles (1); RAMConsult (2)

Previous in Forum: Generator Protection in Neutral and Line   Next in Forum: Under Voltage Problem at DG Sets

Advertisement

Got Something to Say?
Ask a Question
Start a Discussion

Search this Forum
Electrical Engineering:
Go

CR4 Sections
Aerospace
BioMech & BioMed
Chemical & Material Science
Civil Engineering
Communications & Electronics
Education and Engineering Careers
Electrical Engineering
General Discussion
Instrumentation
Manufacturing
Mechanical Engineering
New Technologies & Research
Software & Programming
Sustainable Engineering
Transportation

Site Directories
Forum Directory
Blog Directory
User Group Directory
RSS Feeds

CR4 Rules of Conduct
CR4 FAQ
Site Glossary

Who's Online (151 right now)
Show Members
Advertisement