PRESIDENT HR2600 Service Manual

PRESIDENT LINCOLN (HR 2510) MODSby Roger Peraleshttp://www.gj.net/~peraleswww.president.comDownloaded from www.cbradio.nl

10Modification of the HR2510 Mic buttons to operate the VFONote:This modification is not needed if you have Chipswitched your radio already. The Chips

11 NOTE: If the Up / Down buttons work backwards, exchange the Orange and Brown wires.MOD # 2Mod #2 is the same principal as Mod #1, But uses a Solid

123. Connect the output wire from the Isolation resistor on pin 11 of the 4001 CMOS IC to the top traceon the frequency knob. (the white wire).4. Conn

13Talkback RemovalMOD #1 - The Relay ApproachOne method of Talkback removal is to break the speaker line with a relay.Parts needed :12Volt SPDT relay2

14MOD #2 - The Solid State Approach IAll that is needed is to add a 1N914 Diode from pin 6 of IC103 to the collector of Q125.Connect the cathode of th

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16MOD #3 - The Solid State Approach IIAll that is needed is to add a 1N914 or a 1N4148 Diode connected to a 10k to 100k resistor from pin 6of IC103 to

17HR2510 RIT / Clarifier ModsThe RIT (Receiver Incremental Tuning) on the HR2510 is a Clarifier control to help >tune in= usuallySSB signals that m

18Connect a Frequency counter to TP304. Adjust L318 for 38.695MhzConnect a frequency counter to TP1.Set the Mode switch to USB, adjust L116 for 10.697

19HR2510 Misc. Enhancements.Increasing the Receive Audio IThe HR2510 does not have a by-passed emmiter in the audio circuit. To correct this, Add a 4.

Table of ContentsTo convert the HR2510 to 11 Meter operation: ...

20Adding an external meter to the HR2510To add a needle type meter all you need to do is connect it to C302 on the Microprocessor.

21If you are really interested, I suggest trying the CHIPSWITCH.It gives you :1) 30 memory channels, with temporary channel lockout and repeater offse

2224 MHZ Broadband instructions for your HR2510These instructions are to broadband your radio if you have the 24.000Mhz mod or the ChipSwitchinstalled

23MOD #2 A simpler method...Here is a simpler method of increasing the VCO coverage on the HR2510. If your HR2510 isChipswitched, but doesn't loc

24HR2510 Alignment Instructions - (Taken from the Uniden Service Manual)Alignment of P.L.L. and Carrier Oscillator Portion1. Test equipment required:D

25Alignment of Transmitter Portion1. Test equiptment required:DC Power supply (13.8V) more than 10AAF S.S.G. AM FM (1kHz, 500Hz and 2400Hz)RF VTVM

264 30 mV Mod. VR104 Adjust VR104 for 32.5V reading on the RF VTVM.5 Ditto VR106 Adjust VR106 so that the carrier leakage at USB and LSBbecomes minimu

27Alignment of Receiver Portion1. Test equiptment required:AF VTVM DC Power supply (13.8V)Oscilloscope

28HR2510 Alignment and Test Point LayoutRefer to the HR2510 Alignment instructions(The colors correspond to the adjustment procedure)Synthesizer / Mic

29Main PCB

If you are really interested, I suggest trying the CHIPSWITCH. ...2024 MHZ Broadband instructions

30HR2510 Circuit Block DiagramMicrophone wiring

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4To convert the HR2510 to 11 Meter operation:Remove the cover on the speaker side of the radio. You will need to loosen the 4 screws (2 on each side)t

5To convert the Lincoln to 11 Meter operation:Remove the cover on the speaker side of the radio..Locate the the Microprocessor on the SYNTH PCB.Tie a

6HR2510 Modification for increased MicGainThis mod will increase the AM modulation.The AM modulation adjustment is VR114, which is marked >AMC= on

7President or Uniden HR-2510 Variable Power ModificationThe HR-2510 does not have a varible output power feature as it comes from the manufacturer. Th

8Increasing the power output for the HR2510 1). Remove the top and bottom covers. 2). Locate and remove Q132 & Q134. 3). Replace Q134 with an ECG

9With the radio on USB, Adjust VR112 for 80mA +/- 5mA on the DC Ammeter.After the adjustment is complete, Reinstall the B002(PB-100) jumper board. ]10