300MHz RF module - Page 5 - Electronic Circuits Projects Diagrams Free

Hero999 · 6th January 2007, 03:46 PM

It looks like a good IC, it's easier to use than the MAX7030 and the configureation software is another bonus.

You'll still need to use SMT componants (just less of them) and build it as small as possible.

audioguru · 6th January 2007, 04:55 PM

The modern IC is tiny, has many pins close together and its recommended parts are surface-mount and you said you can't get them.
They say it is for short range.
The IC needs to be programmed.

Hero999 · 6th January 2007, 05:13 PM

Yes it does need to be programmed, but not how you would a PIC. A microcontroller is required to load the configureation data into RAM when it's powered up.

bananasiong · 7th January 2007, 08:06 AM

Yes, I got where to buy the smt components. But I have to order for certain value of components and I have to buy 10 items for each type. Is there any smt crystal?
I think I will use the MAX7030 since I have already order the components. But I don't see any hand made coil or trimmer capacitor, can the receiver receive signal from the transmitter without tuning?

audioguru · 7th January 2007, 10:44 AM

If you can't make them exactly like the manufactured ones then they need to be tuned to the same frequency or the range will be next to nothing.

bananasiong · 7th January 2007, 02:34 PM

then i have to use a trimmer cap for the tank circuit? 2.7 pF trimmer cap is too small, don't know whether can get it or not...

EDIT: Does the amount of the solder affect the stray capacitance or the frequency?

Thanks

audioguru · 7th January 2007, 05:03 PM

Quote:

Originally Posted by bananasiong

then i have to use a trimmer cap for the tank circuit?

It has only a couple of tuned circuits and the values of the capacitors and inductors are specified. They will have a very wide bandwidth and the accurate frequency is determined by the quartz crystal.

Quote:

EDIT: Does the amount of the solder affect the stray capacitance or the frequency?

This is UHF isn't it? It is nearly microwaves. Everything affects a tuned circuit at such a high frequency.

bananasiong · 7th January 2007, 05:17 PM

Oh.. then i have to make sure both the transmitter and receiver to be the same. So difficult..

**Nigel Goodwin** · 7th January 2007, 05:27 PM

Quote:

Originally Posted by bananasiong

Oh.. then i have to make sure both the transmitter and receiver to be the same. So difficult..

Any decent quality of soldering won't be a problem, any changes will be too little to make any difference - however, if your soldering is really poor, it could have an effect?.

bananasiong · 7th January 2007, 05:40 PM

I think my skill is not that poor, but I haven't involved in smt. I think I will cover a layer of solder on the PCB before putting the parts, any good idea?

Thanks

**Nigel Goodwin** · 7th January 2007, 05:43 PM

Tinning it first is perhaps a good idea (as thin as possible), but in any case, using liquid flux will help greatly!.

bananasiong · 7th January 2007, 05:58 PM

Why should it be as thin as possible?

I always use soldering paste/flux. But what's the purpose of using it? Easier to remove the solder?

When soldering, I'm always facing this problem: some oil (or whatever that I don't know) left on the PCB after soldering and removing the components for a few times that makes the solder not to stick on the PCB.

If I use UV PCB, should I remove the film after etching?

Thanks

**Nigel Goodwin** · 7th January 2007, 06:05 PM

Quote:

Originally Posted by bananasiong

Why should it be as thin as possible?

Because the components are supposed to be flat on the board!

Quote:

I always use soldering paste/flux. But what's the purpose of using it? Easier to remove the solder?

It makes the solder flow and 'stick' - please notice I said LIQUID flux, not paste - it's really important for SM work.

Quote:

When soldering, I'm always facing this problem: some oil (or whatever that I don't know) left on the PCB after soldering and removing the components for a few times that makes the solder not to stick on the PCB.

The PCB needs to be PERFECTLY clean and dry, don't even touch the surface with your fingers (the grease stops the solder taking properly).

Quote:

If I use UV PCB, should I remove the film after etching?

Don't know, I don't make PCB's.

Sceadwian · 7th January 2007, 06:07 PM

Flux does several things, it conducts heat to the joint, insulates it (compared to air) and cleans the joint as well. Without flux a lot of thermal oxidation takes place with air and can ruin the joint completly. You should always use a minimum of a denatured alcohol cleaning of the board. Drug store alcohol is a waste of your time as even the best of it (90% isopropyl even if you can find it) is still 10% water. Denatured alcohol is a pure solvent, and usually available at a local hardware store. It disolves particulates well, is cheap enough to use as a flushing liquid to remove small debris, and given even moderatly dry air conditions will completly evaporate.

bananasiong · 7th January 2007, 06:17 PM

How to use liquid flux? Soak the tip into it like soldering paste?

6th January 2007, 03:46 PM	(permalink)
Hero999 Experienced Member	It looks like a good IC, it's easier to use than the MAX7030 and the configureation software is another bonus. You'll still need to use SMT componants (just less of them) and build it as small as possible. __________________ What's so bad about Microsoft? Get Opera it's simply a superb browser.

6th January 2007, 04:55 PM	(permalink)
audioguru Experienced Member	The modern IC is tiny, has many pins close together and its recommended parts are surface-mount and you said you can't get them. They say it is for short range. The IC needs to be programmed. __________________ Uncle $crooge

6th January 2007, 05:13 PM	(permalink)
Hero999 Experienced Member	Yes it does need to be programmed, but not how you would a PIC. A microcontroller is required to load the configureation data into RAM when it's powered up. __________________ What's so bad about Microsoft? Get Opera it's simply a superb browser.

7th January 2007, 08:06 AM	(permalink)
bananasiong Experienced Member	Yes, I got where to buy the smt components. But I have to order for certain value of components and I have to buy 10 items for each type. Is there any smt crystal? I think I will use the MAX7030 since I have already order the components. But I don't see any hand made coil or trimmer capacitor, can the receiver receive signal from the transmitter without tuning? __________________ Superman returns.. Please vote.

7th January 2007, 10:44 AM	(permalink)
audioguru Experienced Member	If you can't make them exactly like the manufactured ones then they need to be tuned to the same frequency or the range will be next to nothing. __________________ Uncle $crooge

7th January 2007, 02:34 PM	(permalink)
bananasiong Experienced Member	then i have to use a trimmer cap for the tank circuit? 2.7 pF trimmer cap is too small, don't know whether can get it or not... EDIT: Does the amount of the solder affect the stray capacitance or the frequency? Thanks __________________ Superman returns.. Please vote.

7th January 2007, 05:17 PM	(permalink)
bananasiong Experienced Member	Oh.. then i have to make sure both the transmitter and receiver to be the same. So difficult.. __________________ Superman returns.. Please vote.

7th January 2007, 05:40 PM	(permalink)
bananasiong Experienced Member	I think my skill is not that poor, but I haven't involved in smt. I think I will cover a layer of solder on the PCB before putting the parts, any good idea? Thanks __________________ Superman returns.. Please vote.

7th January 2007, 05:43 PM	(permalink)
Nigel Goodwin Super Moderator	Tinning it first is perhaps a good idea (as thin as possible), but in any case, using liquid flux will help greatly!. __________________ PIC programmer software, and PIC Tutorials at: http://www.winpicprog.co.uk

7th January 2007, 05:58 PM	(permalink)
bananasiong Experienced Member	Why should it be as thin as possible? I always use soldering paste/flux. But what's the purpose of using it? Easier to remove the solder? When soldering, I'm always facing this problem: some oil (or whatever that I don't know) left on the PCB after soldering and removing the components for a few times that makes the solder not to stick on the PCB. If I use UV PCB, should I remove the film after etching? Thanks __________________ Superman returns.. Please vote.

7th January 2007, 06:07 PM	(permalink)
Sceadwian Experienced Member Blog Entries: 1	Flux does several things, it conducts heat to the joint, insulates it (compared to air) and cleans the joint as well. Without flux a lot of thermal oxidation takes place with air and can ruin the joint completly. You should always use a minimum of a denatured alcohol cleaning of the board. Drug store alcohol is a waste of your time as even the best of it (90% isopropyl even if you can find it) is still 10% water. Denatured alcohol is a pure solvent, and usually available at a local hardware store. It disolves particulates well, is cheap enough to use as a flushing liquid to remove small debris, and given even moderatly dry air conditions will completly evaporate. __________________ Curiosity killed the cat; That's why they have nine lives.

7th January 2007, 06:17 PM	(permalink)
bananasiong Experienced Member	How to use liquid flux? Soak the tip into it like soldering paste? __________________ Superman returns.. Please vote.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Latest
Chip talk	dreamproject	Electronic Projects Design/Ideas/Reviews	8	2nd April 2005 07:24 PM
Motor control interface	dreamproject	Micro Controllers	0	31st March 2005 03:48 AM
controlling laser module via RF receiver	mr. mister	Robotics Chat	1	28th February 2005 03:45 PM
ignition module	induction1	General Electronics Chat	5	24th November 2003 11:34 PM
Safety interlock module	wilfredmike	Electronic Projects Design/Ideas/Reviews	6	2nd November 2003 08:41 PM