background image

  FM10C 35 

THE RAMSEY KIT WARRANTY 

 

1.  GENERAL: 

Notice that this is not a "fine print" warranty.  We want you to understand your rights and ours too!  All Ramsey kits will work if 
assembled properly. The very fact that your kit includes this new manual is your assurance that prior to release of this kit, a 
varied group of knowledgeable people have assembled this kit from scratch using this manual.  During this process, changes 
and additions are noted by each assembler and integrated into the final version of the manual…which you have!  If you need 
help, please read through your manual carefully, all information required to properly build and test your kit is contained within 
the pages!  However, customer satisfaction is our goal, so in the event that you do have a problem, please note the following: 
 

2. DEFECTIVE PARTS: 

It's always easy to blame a part for a problem in your kit.  Before you conclude that a part may be bad, thoroughly check your 
work. Today's semiconductors and passive components have reached incredibly high reliability levels, and it’s sad to say that 
our human construction skills have not!  But on rare occasions a sour component can slip through.  All of our kit parts carry the 
Ramsey Electronics Warranty that they are free from defects for a full ninety (90) days from the date of purchase.  Defective 
parts will be replaced promptly at our expense.  If you suspect any part to be defective, please mail it to our factory for testing 
and replacement.  Please send only the defective part(s), not the entire kit.  The part(s) MUST be returned to us in suitable 
condition for testing. Please be aware that testing can usually determine if the part was truly defective or damaged by assembly 
or usage.  Don't be afraid of telling us that you “damaged it” or “burned it out”, we're all human and in most cases, replacement 
parts are very reasonably priced.  Remember, our goal for over three decades is to have a happy customer, and we’re here to 
work WITH you, not AGAINST you! 
 

3. MISSING PARTS: 

Before assuming a part value is missing, check the parts listing carefully to see if it is a critical value such as a specific coil or 
IC, or whether a RANGE of values is suitable for the component (such as a "100 to 500 uF capacitor").  Often times, common 
sense will solve a mysterious missing part problem.  If you're missing five 10K ohm resistors and received five extra 1K 
resistors, you can pretty much be assured that the “1K ohm” resistors are actually the “missing” 10 K parts ("Hum-m-m, I guess 
the orange band really does look red!")  Ramsey Electronics project kits are packed with pride in the USA by our own staff 
personnel.  While separate QC checks are made on all product kits, we too are human, and once in a great while there is a 
chance something can get through those checks!  If you believe we packed an incorrect part or omitted a part clearly indicated 
in your assembly manual for your Ramsey kit, please contact us with information on the part you need.  Contact our Repair 
Department via telephone, email or writing.  Please have your invoice number and date of purchase handy. 
 

4. REFUNDS: 

All Ramsey products, kit or factory assembled units have an unconditional 10 day (from the date of purchase) return policy to 
examine our products. If you are not satisfied for any reason, you may return your unassembled kit with all the parts and 
instructions, or your factory assembled and tested product, together with your proof of purchase to the factory for a full refund 
less shipping. The return package should be packed securely. Insurance and tracking is highly recommended.  A reminder, this 
applies to unassembled kits.  They must be in the same new condition as received, not partially assembled!  Assembled kits 
cannot be returned for credit.  No RMA’s are required; simply return to Ramsey Electronics LLC, Attn: Product Returns, 590 
Fishers Station Drive, Victor, NY, 14564.  If you have any questions, please contact us at 585-924-4560. 
 

5. FACTORY REPAIR OF ASSEMBLED KITS:

  

Most of us at Ramsey are technically oriented and we do realize that things happen!  Even following the best practices, with all 
of the best intentions, there is that chance that your kit doesn’t work when you have completed it.  Each manual goes into 
detailed troubleshooting based on the specific kit to help you troubleshoot the problem.  We have found that 95% of returned 
kits involved wrongly installed components (wrong part or backwards polarity).  This section of the warranty assumes you have 
gone through all those steps, and have now reached the point that you need to send it back. 
 
To qualify for factory repair of customer assembled kits, the following conditions apply: 

1. 

Kits must not be assembled with acid solder flux 

2. 

Kit boards or circuits must not be modified in any manner from the version received 

3. 

Kits must be fully assembled, not partially assembled.  Our warranty does not include “finishing” your kit! 

4. 

Must include a full description of the problem encountered including the troubleshooting steps you have already done. 

5. 

Must not include non-standard, non-Ramsey accessories, cases, enclosures, knobs, etc. or any batteries. 

6. 

Must include the minimum repair fee of $25 USD in the form of check, money order or credit card authorization. 

7. 

Ramsey Electronics, LLC reserves the right to refuse any repair due to excessive errors in construction methods. 

8. 

If, due to customer construction methods, the repair is estimated to exceed the minimum flat rate, Ramsey Electronics, 
LLC will contact the customer to discuss the repairs needed and to receive authorization and payment for repair prior 
to repair. 

9. 

In the unlikely case that a defective part is found to be the cause of the problem, the repairs will be made at no-charge 
to the customer, and any payments received for repair will be returned or credited back to the customer. 

10.  Properly pack your kit, insure the package, and use a carrier that can be tracked.  Ramsey Electronics, LLC is not 

responsible for any loss or damage in shipment.  Send the package together with your repair fee to the return address 
below. No RMA is required. 

 

6. FACTORY REPAIR FEES:

  

Please understand that our Tech Support Group personnel are not volunteers!  They are a dedicated group of highly trained 
technicians each configured with a very properly equipped test bench.  Upon receipt of a repair, the setup, testing, diagnosis, 
repair, paperwork, and repacking of your kit requires nearly an hour of their time regardless of the size or complexity of the kit!  
The minimum repair fee represents ½ hour Tech Support time at $50/hour USD.  We try to keep all kit repairs within the realm 
of the $25 flat rate whenever possible…and trust us; we exceed that time spent on most kits received more often than not! 
 

7. CONTACT INFORMATION AND RETURN ADDRESS: 

 
 

Technical Questions

 

Product Repair & Returns

 

RAMSEY ELECTRONICS, LLC 

Attn:  Tech Support 

590 Fishers Station Drive 

Victor, NY  14564 

585-924-4560; 585-924-4886 Fax 

[email protected] 

RAMSEY ELECTRONICS, LLC 

Attn:  Repairs 

590 Fishers Station Drive 

Victor, NY  14564 

585-924-4560; 585-924-4886 Fax 

[email protected] 

Summary of Contents for FM10C

Page 1: ...hannel to the scanner and the other to their two way radio Now you can hear what s going on around town up to several blocks away from your house with a simple stereo receiver and adjust the volume of...

Page 2: ...MSEY AMATEUR RADIO KITS DDF1 Doppler Direction Finder HR Series HF All Mode Receivers QRP Series HF CW Transmitters CPO3 Code Practice Oscillator QRP Power Amplifiers RAMSEY MINI KITS Many other kits...

Page 3: ...18 Adjusting your FM10C 20 Using FM10C Within the Home 21 Power Supply Considerations 21 LED Power On Indicator 21 Experimental Broadcasting Projects 22 Antenna Ideas 23 Troubleshooting Guide 24 Appen...

Page 4: ...ality frequency stability and stereo channel separation of this build it yourself FM stereo transmitter If you follow our assembly directions carefully and use your FM10C in accordance with applicable...

Page 5: ...9kHz pilot signal and RF Carrier 88 108 MHz The control of U1 is determined by its surrounding circuitry as described in the following paragraphs Audio We will look only at the left channel circuitry...

Page 6: ...to the transistor Q1 R11 sets the bias or operating point of Q1 R12 is the collector load resistor that develops the output signal and brings in DC power RF Output C23 couples the RF output signal to...

Page 7: ...FM10C 7 FM10C PARTS LAYOUT DIAGRAM...

Page 8: ...electrolytic capacitor C4 INDUCTORS 3 2 2 uH red red gold L1 2 3 1 13 turn air core inductor L5 1 Adjustable shielded inductor coil L4 small square silver can RESISTORS 1 200 ohm 1 2 watt red black b...

Page 9: ...eet 1 Button for DPDT switch REQUIRED NOT SUPPLIED 9 volt alkaline or heavy duty battery Shielded stereo audio cables Line level output audio source such as a tape deck or CD player OPTIONAL LED power...

Page 10: ...at the traces to which you are soldering heating both wires and pads simultaneously Apply the solder to the iron and the pad when the pad is hot enough to melt the solder The finished joint should loo...

Page 11: ...e us a call at the factory We will be happy to help you with any problems you may run into This is a mixed signal project meaning there is digital audio and RF circuitry all in one unit As with all RF...

Page 12: ...ight chan nel of the modulator IC Seat it flat before soldering 10 Install R4 another 1K ohm trimmer potentiometer marked 102 This pot is used to adjust the audio level to the left channel of the modu...

Page 13: ...has no polarity require ments so its leads can be placed in either of the two holes 20 Install crystal strap using a scrap component lead looped around the crystal and placed through the other two cry...

Page 14: ...ator 38 Install C17 a 001uF ceramic capacitor marked 102 39 Install C19 a 10pF ceramic capacitor marked 10 40 Install shielded slug tuned coil L4 The larger tabs secure the shield can to the ground fo...

Page 15: ...ll 53 Install R13 a 1K ohm resistor brown black red 54 Install L5 a 13 turn air core coil Just as with the other inductors polarity is not an issue 55 Install ANT1 a telescoping antenna Insert the scr...

Page 16: ...p Also look for potential solder bridges the parts layout diagram can help with that You may want to hurry and get the kit powered up but any thing you find now will save you a lot more trouble later...

Page 17: ...the groove side is on your left 2 Place the front panel in the groove of the case bottom in the side that is facing you 3 Place the circuit board in the case bottom so that the DPST switch comes thro...

Page 18: ...FM10A 18 FM10C REV2 1 SCHEMATIC DIAGRAM...

Page 19: ...FM10C 19...

Page 20: ...cess for the right channel and R3 Hooking up an audio source to your FM10C is really quite simple However there are some general rules A terribly distorted sound is a sign of too much audio level Simp...

Page 21: ...ility to suppress unwanted AC line hum Various plug in adapters and power supplies in the 6 to 12 volt range may be tried but make sure the unit has DC output positive tip and is not merely a transfor...

Page 22: ...2 It would be an excellent class family or Scout project 3 Commercially made stereo mixing consoles while much less expensive today than a decade ago will cost much more than did your FM10C kit 4 The...

Page 23: ...nnected to the center conductor of the coax should be the upper higher end If young children will be around the set up a flexible wire antenna is preferable rather than rigid tubing A ground plane ant...

Page 24: ...lation is beyond the original purpose of this kit and the safety standards intended for all Ramsey kits and because we have not tested the FM 10A in such an installation we cannot provide further deta...

Page 25: ...of Documents at 202 512 3238 or fax at 202 512 2250 To order the correct document ask for CFR Title 17 Parts 1 to 19 The cost is 24 00 Master Card and Visa accepted In the United States this is how t...

Page 26: ...id any and all interference to licensed FM broadcast transmission and reception This instruction manual gives you practical advice on how to do a good job of finding a clear frequency if one is availa...

Page 27: ...eneral conditions of operation b Operation is subject to the conditions that no harmful interference is caused and that interference must be accepted that may be caused by the operation of an authoriz...

Page 28: ...but the field strength voltage is only halved Using this theory we can construct a simple chart to show the maximum permitted performance of a non licensed FM band transmitter The theoretical figures...

Page 29: ...easy the numbers would get too cumbersome if we discussed your possible signal coverage in terms of square feet or square meters 2 It s very easy to see that your signal can easily and legally serve...

Page 30: ...ower transmitter such as the FM10C The main point is that you may not cause any interference whatso ever to licensed broadcast services and that you must be willing to put up with any interference tha...

Page 31: ...C is toughest about clandestine transmission which cost time and money to track down 10 Do not assume that the mere fact that you purchased this kit gives you any specific right to use it for any purp...

Page 32: ...pose of this kit manual will show you many legal uses of radio transmitting devices which do not require licensing either amateur or commercial To provide more personal and club radio learning opportu...

Page 33: ...vpp Line Level Pre emphasis 75uS or 50uS component selected Stereo Separation 45 dB typical Power Supply Requirements Jack 2 1mm center External Supply Voltage 5 to 20 VDC External Supply Current 60mA...

Page 34: ...____________ ______________________________________________________________ ______________________________________________________________ _____________________________________________________________...

Page 35: ...actory for a full refund less shipping The return package should be packed securely Insurance and tracking is highly recommended A reminder this applies to unassembled kits They must be in the same ne...

Page 36: ...TOOLS Soldering Iron Thin Rosin Core Solder Needle Nose Pliers Small Diagonal Cutters ADDITIONAL SUGGESTED ITEMS Helping Hands Holder Desoldering Braid TOTAL SOLDER POINTS 151 ESTIMATED ASSEMBLY TIME...

Reviews: