<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>000120 - Disclosure - Note 7 - Loan Payable</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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</LabelSeparator><Level>2</Level><ElementName>vuoc_LoanPayableDisclosure</ElementName><ElementPrefix>vuoc_</ElementPrefix><IsBaseElement>false</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="D130101_130630" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;!--egx--&gt;&lt;p style='margin:0in;margin-bottom:.0001pt;text-autospace:none'&gt;&lt;b&gt;NOTE 7 &amp;#150; LOANS PAYABLE&lt;/b&gt;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-autospace:none'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-autospace:none'&gt;On December 20, 2012, we received gross proceeds of $100,000 pursuant to the terms of a Loan Agreement dated December 20, 2012.&amp;#160; The loan is secured by a Deed of Assignment for certain inventory and all proceeds from the sale of the inventory.&amp;#160; The loan is payable on June 23, 2013, six months from the date of the agreement.&amp;#160; We prepaid interest of $25,000 for the term of the loan and $15,000 for loan costs, which are being amortized over the life of the note.&amp;#160; We recognized $15,838 and $0 of interest expense and $28,000 and $0 for loan cost amortization within interest expense for the three and six months ended June 30, 2013 and 2012, respectively.&amp;#160; On June 23, 2013 we did not repay the loan and it is in default.&amp;#160; As a result of the default, the interest rate on the loan is 109.5% per annum from the date of default.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-autospace:none'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-autospace:none'&gt;Total principal payments for future years for the Convertible Debentures described in Note 5 and the Loan Payable are as follows as of June 30, 2013:&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-autospace:none'&gt;&amp;nbsp;&lt;/p&gt; &lt;div align="center"&gt; &lt;table border="0" cellspacing="0" cellpadding="0" style='margin-left:4.65pt;border-collapse:collapse'&gt; &lt;tr style='height:12.75pt'&gt; &lt;td valign="bottom" style='padding:0in 5.4pt 0in 5.4pt;height:12.75pt'&gt;&lt;/td&gt; &lt;td valign="bottom" style='padding:0in 5.4pt 0in 5.4pt;height:12.75pt'&gt;&lt;/td&gt; &lt;td valign="bottom" style='border:none;border-bottom:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:12.75pt'&gt; &lt;p align="center" style='margin:0in;margin-bottom:.0001pt;text-align:center'&gt;&lt;b&gt;June 30, 2013&lt;/b&gt;&lt;/p&gt; &lt;/td&gt; &lt;/tr&gt; &lt;tr style='height:12.75pt'&gt; &lt;td valign="bottom" style='padding:0in 5.4pt 0in 5.4pt;height:12.75pt'&gt; &lt;p align="right" style='margin:0in;margin-bottom:.0001pt;text-align:right'&gt;2013&lt;/p&gt; &lt;/td&gt; &lt;td valign="bottom" style='padding:0in 5.4pt 0in 5.4pt;height:12.75pt'&gt;&lt;/td&gt; &lt;td valign="bottom" style='padding:0in 5.4pt 0in 5.4pt;height:12.75pt'&gt; &lt;p style='margin:0in;margin-bottom:.0001pt'&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; 4,094,213 &lt;/p&gt; &lt;/td&gt; &lt;/tr&gt; &lt;tr style='height:13.5pt'&gt; &lt;td valign="bottom" style='padding:0in 5.4pt 0in 5.4pt;height:13.5pt'&gt;&lt;/td&gt; &lt;td valign="bottom" style='padding:0in 5.4pt 0in 5.4pt;height:13.5pt'&gt;&lt;/td&gt; &lt;td valign="bottom" style='border-top:solid windowtext 1.0pt;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:none;padding:0in 5.4pt 0in 5.4pt;height:13.5pt'&gt; &lt;p style='margin:0in;margin-bottom:.0001pt'&gt;&amp;#160;$&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; &amp;#160;&amp;#160;&amp;#160;&amp;#160;4,094,213 &lt;/p&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; &lt;/div&gt; &lt;p align="center" style='margin:0in;margin-bottom:.0001pt;text-align:center;text-autospace:none'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-autospace:none'&gt;On May 16, 2013 we received gross proceeds of $100,000 pursuant to a Loan Agreement as of that date.&amp;#160; The term of the loan was for 30 days.&amp;#160; Total interest for the 30 day term was $10,000.&amp;#160; On June 18, 2013 the holder of the loan converted the $110,000 of principal and interest in our unit private placement as further described in Note 8 at a conversion price of $1.50 per share into 73,333 shares of common stock and three-year warrants to purchase common stock at an exercise price of $2.00 per share.&amp;#160; The fair value of the common stock was $95,333 based on the market prices of our common stock on the date of conversion of $1.30 per share.&amp;#160; The fair value of the three year warrants to purchase 73,333 shares of our common stock at an exercise price of $2.00 per share was $43,687. We recognized a loss on debt conversion for the three and six months ended June 30, 2013 in the amount of $29,020.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-autospace:none'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-autospace:none'&gt;The fair value of the warrants issued upon the conversion was computed using the Black Scholes Option Pricing model using the following assumptions &amp;#150; expected life &amp;#150; 3 years, risk free interest rate &amp;#150; 0.42%, volatility &amp;#150; 91.4%, and an expected dividend rate of 0%.&lt;/p&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>No authoritative reference available.</ElementDefenition><ElementReferences>No definition available.</ElementReferences><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Note 7 - Loan Payable</Label></Row></Rows><Footnotes /><IsEquityReport>false</IsEquityReport><ReportName>Note 7 - Loan Payable</ReportName><MonetaryRoundingLevel>UnKnown</MonetaryRoundingLevel><SharesRoundingLevel>UnKnown</SharesRoundingLevel><PerShareRoundingLevel>UnKnown</PerShareRoundingLevel><ExchangeRateRoundingLevel>UnKnown</ExchangeRateRoundingLevel><HasCustomUnits>true</HasCustomUnits><IsEmbedReport>false</IsEmbedReport><IsMultiCurrency>false</IsMultiCurrency><ReportType>Sheet</ReportType><RoleURI>http://vu1corporation.com/20130630/role/idr_DisclosureNote7LoanPayable</RoleURI><NumberOfCols>1</NumberOfCols><NumberOfRows>2</NumberOfRows></InstanceReport>
